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fea681da | 1 | .\" Copyright (C) 1994, 1995 by Daniel Quinlan (quinlan@yggdrasil.com) |
b4e9ee8f | 2 | .\" and Copyright (C) 2002-2008 Michael Kerrisk <mtk.manpages@gmail.com> |
fea681da MK |
3 | .\" with networking additions from Alan Cox (A.Cox@swansea.ac.uk) |
4 | .\" and scsi additions from Michael Neuffer (neuffer@mail.uni-mainz.de) | |
5 | .\" and sysctl additions from Andries Brouwer (aeb@cwi.nl) | |
6 | .\" and System V IPC (as well as various other) additions from | |
c11b1abf | 7 | .\" Michael Kerrisk <mtk.manpages@gmail.com> |
fea681da | 8 | .\" |
1dd72f9c | 9 | .\" %%%LICENSE_START(GPLv2+_DOC_FULL) |
fea681da MK |
10 | .\" This is free documentation; you can redistribute it and/or |
11 | .\" modify it under the terms of the GNU General Public License as | |
12 | .\" published by the Free Software Foundation; either version 2 of | |
13 | .\" the License, or (at your option) any later version. | |
14 | .\" | |
15 | .\" The GNU General Public License's references to "object code" | |
16 | .\" and "executables" are to be interpreted as the output of any | |
17 | .\" document formatting or typesetting system, including | |
18 | .\" intermediate and printed output. | |
19 | .\" | |
20 | .\" This manual is distributed in the hope that it will be useful, | |
21 | .\" but WITHOUT ANY WARRANTY; without even the implied warranty of | |
22 | .\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
23 | .\" GNU General Public License for more details. | |
24 | .\" | |
25 | .\" You should have received a copy of the GNU General Public | |
c715f741 MK |
26 | .\" License along with this manual; if not, see |
27 | .\" <http://www.gnu.org/licenses/>. | |
6a8d8745 | 28 | .\" %%%LICENSE_END |
fea681da MK |
29 | .\" |
30 | .\" Modified 1995-05-17 by faith@cs.unc.edu | |
31 | .\" Minor changes by aeb and Marty Leisner (leisner@sdsp.mc.xerox.com). | |
32 | .\" Modified 1996-04-13, 1996-07-22 by aeb@cwi.nl | |
33 | .\" Modified 2001-12-16 by rwhron@earthlink.net | |
34 | .\" Modified 2002-07-13 by jbelton@shaw.ca | |
35 | .\" Modified 2002-07-22, 2003-05-27, 2004-04-06, 2004-05-25 | |
c11b1abf | 36 | .\" by Michael Kerrisk <mtk.manpages@gmail.com> |
5d6d14a0 MK |
37 | .\" 2004-11-17, mtk -- updated notes on /proc/loadavg |
38 | .\" 2004-12-01, mtk, rtsig-max and rtsig-nr went away in 2.6.8 | |
568105c6 MK |
39 | .\" 2004-12-14, mtk, updated 'statm', and fixed error in order of list |
40 | .\" 2005-05-12, mtk, updated 'stat' | |
6d64ca9c | 41 | .\" 2005-07-13, mtk, added /proc/sys/fs/mqueue/* |
363f747c MK |
42 | .\" 2005-09-16, mtk, Added /proc/sys/fs/suid_dumpable |
43 | .\" 2005-09-19, mtk, added /proc/zoneinfo | |
b4e9ee8f | 44 | .\" 2005-03-01, mtk, moved /proc/sys/fs/mqueue/* material to mq_overview.7. |
69119dc7 MK |
45 | .\" 2008-06-05, mtk, Added /proc/[pid]/oom_score, /proc/[pid]/oom_adj, |
46 | .\" /proc/[pid]/limits, /proc/[pid]/mountinfo, /proc/[pid]/mountstats, | |
47 | .\" and /proc/[pid]/fdinfo/*. | |
48 | .\" 2008-06-19, mtk, Documented /proc/[pid]/status. | |
cc2d5c36 | 49 | .\" 2008-07-15, mtk, added /proc/config.gz |
363f747c | 50 | .\" |
bea08fec | 51 | .\" FIXME . cross check against Documentation/filesystems/proc.txt |
c13182ef | 52 | .\" to see what information could be imported from that file |
c533af9d | 53 | .\" into this file. |
fea681da | 54 | .\" |
3df541c0 | 55 | .TH PROC 5 2016-07-17 "Linux" "Linux Programmer's Manual" |
fea681da | 56 | .SH NAME |
9ee4a2b6 | 57 | proc \- process information pseudo-filesystem |
fea681da MK |
58 | .SH DESCRIPTION |
59 | The | |
60 | .I proc | |
ac8727b6 | 61 | filesystem is a pseudo-filesystem which provides an interface to |
c13182ef MK |
62 | kernel data structures. |
63 | It is commonly mounted at | |
fea681da | 64 | .IR /proc . |
c13182ef | 65 | Most of it is read-only, but some files allow kernel variables to be |
fea681da | 66 | changed. |
fee59977 MK |
67 | .SS Mount options |
68 | The | |
69 | .I proc | |
70 | filesystem supports the following mount options: | |
71 | .TP | |
72 | .BR hidepid "=\fIn\fP (since Linux 3.3)" | |
73 | .\" commit 0499680a42141d86417a8fbaa8c8db806bea1201 | |
74 | This option controls who can access the information in | |
75 | .IR /proc/[pid] | |
76 | directories. | |
77 | The argument, | |
78 | .IR n , | |
79 | is one of the following values: | |
80 | .RS | |
81 | .TP 4 | |
82 | 0 | |
83 | Everybody may access all | |
84 | .IR /proc/[pid] | |
85 | directories. | |
86 | This is the traditional behavior, | |
87 | and the default if this mount option is not specified. | |
88 | .TP | |
89 | 1 | |
90 | Users may not access files and subdirectories inside any | |
91 | .IR /proc/[pid] | |
92 | directories but their own (the | |
93 | .IR /proc/[pid] | |
94 | directories themselves remain visible). | |
95 | Sensitive files such as | |
97949440 | 96 | .IR /proc/[pid]/cmdline |
fee59977 | 97 | and |
97949440 | 98 | .IR /proc/[pid]/status |
fee59977 MK |
99 | are now protected against other users. |
100 | This makes it impossible to learn whether any user is running a | |
101 | specific program | |
102 | (so long as the program doesn't otherwise reveal itself by its behavior). | |
103 | .\" As an additional bonus, since | |
97949440 | 104 | .\" .IR /proc/[pid]/cmdline |
fee59977 MK |
105 | .\" is unaccessible for other users, |
106 | .\" poorly written programs passing sensitive information via | |
107 | .\" program arguments are now protected against local eavesdroppers. | |
108 | .TP | |
109 | 2 | |
110 | As for mode 1, but in addition the | |
111 | .IR /proc/[pid] | |
112 | directories belonging to other users become invisible. | |
113 | This means that | |
114 | .IR /proc/[pid] | |
115 | entries can no longer be used to discover the PIDs on the system. | |
116 | This doesn't hide the fact that a process with a specific PID value exists | |
117 | (it can be learned by other means, for example, by "kill -0 $PID"), | |
118 | but it hides a process's UID and GID, | |
119 | which could otherwise be learned by employing | |
120 | .BR stat (2) | |
121 | on a | |
122 | .IR /proc/[pid] | |
123 | directory. | |
124 | This greatly complicates an attacker's task of gathering | |
125 | information about running processes (e.g., discovering whether | |
126 | some daemon is running with elevated privileges, | |
127 | whether another user is running some sensitive program, | |
128 | whether other users are running any program at all, and so on). | |
129 | .RE | |
130 | .TP | |
131 | .BR gid "=\fIgid\fP (since Linux 3.3)" | |
132 | .\" commit 0499680a42141d86417a8fbaa8c8db806bea1201 | |
133 | Specifies the ID of a group whose members are authorized to | |
134 | learn process information otherwise prohibited by | |
135 | .BR hidepid | |
95b1c1d1 | 136 | (i.e., users in this group behave as though |
fee59977 MK |
137 | .I /proc |
138 | was mounted with | |
95b1c1d1 | 139 | .IR hidepid=0 ). |
fee59977 MK |
140 | This group should be used instead of approaches such as putting |
141 | nonroot users into the | |
142 | .BR sudoers (5) | |
143 | file. | |
144 | .SS Files and directories | |
ac8727b6 | 145 | The following list describes many of the files and directories under the |
743638fd MK |
146 | .I /proc |
147 | hierarchy. | |
fea681da MK |
148 | .PD 1 |
149 | .TP | |
69119dc7 | 150 | .I /proc/[pid] |
fea681da MK |
151 | There is a numerical subdirectory for each running process; the |
152 | subdirectory is named by the process ID. | |
153 | Each such subdirectory contains the following | |
154 | pseudo-files and directories. | |
b7a42567 MK |
155 | .TP |
156 | .I /proc/[pid]/attr | |
157 | .\" https://lwn.net/Articles/28222/ | |
158 | .\" From: Stephen Smalley <sds@epoch.ncsc.mil> | |
159 | .\" To: LKML and others | |
160 | .\" Subject: [RFC][PATCH] Process Attribute API for Security Modules | |
161 | .\" Date: 08 Apr 2003 16:17:52 -0400 | |
162 | .\" | |
b3fb99e8 MK |
163 | .\" http://www.nsa.gov/research/_files/selinux/papers/module/x362.shtml |
164 | .\" | |
b7a42567 MK |
165 | The files in this directory provide an API for security modules. |
166 | The contents of this directory are files that can be read and written | |
167 | in order to set security-related attributes. | |
168 | This directory was added to support SELinux, | |
169 | but the intention was that the API be general enough to support | |
170 | other security modules. | |
171 | For the purpose of explanation, | |
172 | examples of how SELinux uses these files are provided below. | |
173 | ||
174 | This directory is present only if the kernel was configured with | |
175 | .BR CONFIG_SECURITY . | |
176 | .TP | |
177 | .IR /proc/[pid]/attr/current " (since Linux 2.6.0)" | |
178 | The contents of this file represent the current | |
179 | security attributes of the process. | |
180 | ||
fd44bdc7 TY |
181 | In SELinux, this file is used to get the security context of a process. |
182 | Prior to Linux 2.6.11, this file could not be used to set the security | |
183 | context (a write was always denied), since SELinux limited process security | |
184 | transitions to | |
b7a42567 MK |
185 | .BR execve (2) |
186 | (see the description of | |
187 | .IR /proc/[pid]/attr/exec , | |
188 | below). | |
fd44bdc7 TY |
189 | Since Linux 2.6.11, SELinux lifted this restriction and began supporting |
190 | "set" operations via writes to this node if authorized by policy, | |
191 | although use of this operation is only suitable for applications that are | |
192 | trusted to maintain any desired separation between the old and new security | |
b6620a25 MK |
193 | contexts. |
194 | Prior to Linux 2.6.28, SELinux did not allow threads within a | |
fd44bdc7 TY |
195 | multi-threaded process to set their security context via this node |
196 | as it would yield an inconsistency among the security contexts of the | |
b6620a25 MK |
197 | threads sharing the same memory space. |
198 | Since Linux 2.6.28, SELinux lifted | |
fd44bdc7 | 199 | this restriction and began supporting "set" operations for threads within |
b6620a25 | 200 | a multithreaded process if the new security context is bounded by the old |
fd44bdc7 TY |
201 | security context, where the bounded relation is defined in policy and |
202 | guarantees that the new security context has a subset of the permissions | |
203 | of the old security context. | |
b7a42567 MK |
204 | Other security modules may choose to support "set" operations via |
205 | writes to this node. | |
206 | .TP | |
207 | .IR /proc/[pid]/attr/exec " (since Linux 2.6.0)" | |
208 | This file represents the attributes to assign to the | |
209 | process upon a subsequent | |
210 | .BR execve (2). | |
211 | ||
212 | In SELinux, | |
213 | this is needed to support role/domain transitions, and | |
214 | .BR execve (2) | |
215 | is the preferred point to make such transitions because it offers better | |
216 | control over the initialization of the process in the new security label | |
217 | and the inheritance of state. | |
218 | In SELinux, this attribute is reset on | |
219 | .BR execve (2) | |
220 | so that the new program reverts to the default behavior for any | |
221 | .BR execve (2) | |
222 | calls that it may make. | |
223 | In SELinux, a process can set | |
224 | only its own | |
225 | .I /proc/[pid]/attr/exec | |
226 | attribute. | |
227 | .TP | |
228 | .IR /proc/[pid]/attr/fscreate " (since Linux 2.6.0)" | |
229 | This file represents the attributes to assign to files | |
230 | created by subsequent calls to | |
231 | .BR open (2), | |
232 | .BR mkdir (2), | |
233 | .BR symlink (2), | |
234 | and | |
235 | .BR mknod (2) | |
236 | ||
237 | SELinux employs this file to support creation of a file | |
238 | (using the aforementioned system calls) | |
239 | in a secure state, | |
240 | so that there is no risk of inappropriate access being obtained | |
241 | between the time of creation and the time that attributes are set. | |
242 | In SELinux, this attribute is reset on | |
243 | .BR execve (2), | |
244 | so that the new program reverts to the default behavior for | |
245 | any file creation calls it may make, but the attribute will persist | |
246 | across multiple file creation calls within a program unless it is | |
247 | explicitly reset. | |
248 | In SELinux, a process can set only its own | |
249 | .IR /proc/[pid]/attr/fscreate | |
250 | attribute. | |
251 | .TP | |
252 | .IR /proc/[pid]/attr/prev " (since Linux 2.6.0)" | |
253 | This file contains the security context of the process before the last | |
254 | .BR execve (2); | |
255 | that is, the previous value of | |
256 | .IR /proc/[pid]/attr/current . | |
666db07e MK |
257 | .TP |
258 | .IR /proc/[pid]/attr/keycreate " (since Linux 2.6.18)" | |
259 | .\" commit 4eb582cf1fbd7b9e5f466e3718a59c957e75254e | |
260 | .\" /Documentation/keys.txt | |
261 | If a process writes a security context into this file, | |
262 | all subsequently created keys | |
263 | .RB ( add_key (2)) | |
264 | will be labeled with this context. | |
265 | For further information, see the kernel source file | |
266 | .IR Documentation/keys.txt . | |
2702dc21 MK |
267 | .TP |
268 | .IR /proc/[pid]/attr/socketcreate " (since Linux 2.6.18)" | |
269 | .\" commit 42c3e03ef6b298813557cdb997bd6db619cd65a2 | |
270 | If a process writes a security context into this file, | |
271 | all subsequently created sockets will be labeled with this context. | |
b3fb99e8 MK |
272 | .\" |
273 | .\" FIXME Describe /proc/[pid]/autogroup | |
274 | .\" 2.6.38 | |
275 | .\" commit 5091faa449ee0b7d73bc296a93bca9540fc51d0a | |
276 | .\" CONFIG_SCHED_AUTOGROUP | |
b4e9ee8f | 277 | .\" |
fea681da | 278 | .TP |
69119dc7 | 279 | .IR /proc/[pid]/auxv " (since 2.6.0-test7)" |
857f1942 | 280 | This contains the contents of the ELF interpreter information passed |
c13182ef | 281 | to the process at exec time. |
857f1942 | 282 | The format is one \fIunsigned long\fP ID |
c13182ef | 283 | plus one \fIunsigned long\fP value for each entry. |
857f1942 | 284 | The last entry contains two zeros. |
4c69c692 MK |
285 | See also |
286 | .BR getauxval (3). | |
82664739 MK |
287 | |
288 | Permission to access this file is governed by a ptrace access mode | |
289 | .B PTRACE_MODE_READ_FSCREDS | |
290 | check; see | |
291 | .BR ptrace (2). | |
b5d204d0 | 292 | .TP |
8d708d6b | 293 | .IR /proc/[pid]/cgroup " (since Linux 2.6.24)" |
5c2181ad MK |
294 | See |
295 | .BR cgroups (7). | |
76e0451c MK |
296 | .TP |
297 | .IR /proc/[pid]/clear_refs " (since Linux 2.6.22)" | |
298 | .\" commit b813e931b4c8235bb42e301096ea97dbdee3e8fe (2.6.22) | |
299 | .\" commit 398499d5f3613c47f2143b8c54a04efb5d7a6da9 (2.6.32) | |
300 | .\" commit 040fa02077de01c7e08fa75be6125e4ca5636011 (3.11) | |
b4e9ee8f | 301 | .\" |
b4e9ee8f | 302 | .\" "Clears page referenced bits shown in smaps output" |
76e0451c MK |
303 | .\" write-only, writable only by the owner of the process |
304 | ||
305 | This is a write-only file, writable only by owner of the process. | |
306 | ||
307 | The following values may be written to the file: | |
308 | .RS | |
309 | .TP | |
310 | 1 (since Linux 2.6.22) | |
311 | .\" Internally: CLEAR_REFS_ALL | |
312 | Reset the PG_Referenced and ACCESSED/YOUNG | |
313 | bits for all the pages associated with the process. | |
314 | (Before kernel 2.6.32, writing any nonzero value to this file | |
315 | had this effect.) | |
316 | .TP | |
317 | 2 (since Linux 2.6.32) | |
318 | .\" Internally: CLEAR_REFS_ANON | |
319 | Reset the PG_Referenced and ACCESSED/YOUNG | |
320 | bits for all anonymous pages associated with the process. | |
321 | .TP | |
322 | 3 (since Linux 2.6.32) | |
323 | .\" Internally: CLEAR_REFS_MAPPED | |
324 | Reset the PG_Referenced and ACCESSED/YOUNG | |
325 | bits for all file-mapped pages associated with the process. | |
326 | .RE | |
327 | .IP | |
328 | Clearing the PG_Referenced and ACCESSED/YOUNG bits provides a method | |
329 | to measure approximately how much memory a process is using. | |
322d49fb | 330 | One first inspects the values in the "Referenced" fields |
76e0451c MK |
331 | for the VMAs shown in |
332 | .IR /proc/[pid]/smaps | |
333 | to get an idea of the memory footprint of the | |
334 | process. | |
335 | One then clears the PG_Referenced and ACCESSED/YOUNG bits | |
336 | and, after some measured time interval, | |
322d49fb | 337 | once again inspects the values in the "Referenced" fields |
76e0451c MK |
338 | to get an idea of the change in memory footprint of the |
339 | process during the measured interval. | |
340 | If one is interested only in inspecting the selected mapping types, | |
341 | then the value 2 or 3 can be used instead of 1. | |
342 | ||
343 | A further value can be written to affect a different bit: | |
344 | .RS | |
345 | .TP | |
346 | 4 (since Linux 3.11) | |
347 | Clear the soft-dirty bit for all the pages associated with the process. | |
348 | .\" Internally: CLEAR_REFS_SOFT_DIRTY | |
349 | This is used (in conjunction with | |
350 | .IR /proc/[pid]/pagemap ) | |
351 | by the check-point restore system to discover which pages of a process | |
352 | have been dirtied since the file | |
353 | .IR /proc/[pid]/clear_refs | |
354 | was written to. | |
355 | .RE | |
356 | .IP | |
357 | Writing any value to | |
358 | .IR /proc/[pid]/clear_refs | |
359 | other than those listed above has no effect. | |
360 | ||
361 | The | |
362 | .IR /proc/[pid]/clear_refs | |
363 | file is present only if the | |
364 | .B CONFIG_PROC_PAGE_MONITOR | |
365 | kernel configuration option is enabled. | |
857f1942 | 366 | .TP |
69119dc7 | 367 | .I /proc/[pid]/cmdline |
6975c16e | 368 | This read-only file holds the complete command line for the process, |
b447cd58 MK |
369 | unless the process is a zombie. |
370 | .\" In 2.3.26, this also used to be true if the process was swapped out. | |
371 | In the latter case, there is nothing in this file: | |
75b94dc3 | 372 | that is, a read on this file will return 0 characters. |
b447cd58 | 373 | The command-line arguments appear in this file as a set of |
6596d270 MK |
374 | strings separated by null bytes (\(aq\\0\(aq), |
375 | with a further null byte after the last string. | |
32d7ef00 MK |
376 | .TP |
377 | .IR /proc/[pid]/comm " (since Linux 2.6.33)" | |
378 | .\" commit 4614a696bd1c3a9af3a08f0e5874830a85b889d4 | |
379 | This file exposes the process's | |
380 | .I comm | |
381 | value\(emthat is, the command name associated with the process. | |
382 | Different threads in the same process may have different | |
383 | .I comm | |
384 | values, accessible via | |
385 | .IR /proc/[pid]/task/[tid]/comm . | |
386 | A thread may modify its | |
387 | .I comm | |
388 | value, or that of any of other thread in the same thread group (see | |
389 | the discussion of | |
390 | .B CLONE_THREAD | |
391 | in | |
392 | .BR clone (2)), | |
393 | by writing to the file | |
394 | .IR /proc/self/task/[tid]/comm . | |
395 | Strings longer than | |
396 | .B TASK_COMM_LEN | |
397 | (16) characters are silently truncated. | |
398 | ||
ef4f4031 | 399 | This file provides a superset of the |
32d7ef00 MK |
400 | .BR prctl (2) |
401 | .B PR_SET_NAME | |
402 | and | |
403 | .B PR_GET_NAME | |
404 | operations, and is employed by | |
405 | .BR pthread_setname_np (3) | |
406 | when used to rename threads other than the caller. | |
fea681da | 407 | .TP |
7e07d950 | 408 | .IR /proc/[pid]/coredump_filter " (since Linux 2.6.23)" |
b4e9ee8f MK |
409 | See |
410 | .BR core (5). | |
5c411b17 | 411 | .TP |
7e07d950 MK |
412 | .IR /proc/[pid]/cpuset " (since Linux 2.6.12)" |
413 | .\" and/proc/[pid]/task/[tid]/cpuset | |
5c411b17 MK |
414 | See |
415 | .BR cpuset (7). | |
b4e9ee8f | 416 | .TP |
69119dc7 | 417 | .I /proc/[pid]/cwd |
c13182ef | 418 | This is a symbolic link to the current working directory of the process. |
59a40ed7 MK |
419 | To find out the current working directory of process 20, |
420 | for instance, you can do this: | |
fea681da | 421 | |
59a40ed7 | 422 | .in +4n |
fea681da | 423 | .nf |
b43a3b30 | 424 | .RB "$" " cd /proc/20/cwd; /bin/pwd" |
fea681da | 425 | .fi |
59a40ed7 | 426 | .in |
fea681da | 427 | |
c13182ef MK |
428 | Note that the |
429 | .I pwd | |
e7b489f0 | 430 | command is often a shell built-in, and might |
c13182ef | 431 | not work properly. |
743638fd MK |
432 | In |
433 | .BR bash (1), | |
434 | you may use | |
435 | .IR "pwd\ \-P" . | |
afcaf646 MK |
436 | |
437 | .\" The following was still true as at kernel 2.6.13 | |
c13182ef MK |
438 | In a multithreaded process, the contents of this symbolic link |
439 | are not available if the main thread has already terminated | |
afcaf646 | 440 | (typically by calling |
59a40ed7 | 441 | .BR pthread_exit (3)). |
b902fe18 MK |
442 | |
443 | Permission to dereference or read | |
444 | .RB ( readlink (2)) | |
445 | this symbolic link is governed by a ptrace access mode | |
446 | .B PTRACE_MODE_READ_FSCREDS | |
447 | check; see | |
448 | .BR ptrace (2). | |
fea681da | 449 | .TP |
69119dc7 | 450 | .I /proc/[pid]/environ |
fea681da | 451 | This file contains the environment for the process. |
f81fb444 | 452 | The entries are separated by null bytes (\(aq\\0\(aq), |
b4e9ee8f | 453 | and there may be a null byte at the end. |
fea681da | 454 | Thus, to print out the environment of process 1, you would do: |
a08ea57c | 455 | .in +4n |
fea681da | 456 | .nf |
a08ea57c | 457 | |
13912780 | 458 | .RB "$" " strings /proc/1/environ" |
fea681da | 459 | .fi |
a08ea57c | 460 | .in |
82664739 MK |
461 | |
462 | Permission to access this file is governed by a ptrace access mode | |
463 | .B PTRACE_MODE_READ_FSCREDS | |
464 | check; see | |
465 | .BR ptrace (2). | |
fea681da | 466 | .TP |
69119dc7 | 467 | .I /proc/[pid]/exe |
fea681da | 468 | Under Linux 2.2 and later, this file is a symbolic link |
2d7195b8 | 469 | containing the actual pathname of the executed command. |
c13182ef MK |
470 | This symbolic link can be dereferenced normally; attempting to open |
471 | it will open the executable. | |
472 | You can even type | |
69119dc7 | 473 | .I /proc/[pid]/exe |
06dd061c | 474 | to run another copy of the same executable that is being run by |
69119dc7 | 475 | process [pid]. |
7e3c767a GJ |
476 | If the pathname has been unlinked, the symbolic link will contain the |
477 | string \(aq(deleted)\(aq appended to the original pathname. | |
afcaf646 | 478 | .\" The following was still true as at kernel 2.6.13 |
c13182ef MK |
479 | In a multithreaded process, the contents of this symbolic link |
480 | are not available if the main thread has already terminated | |
afcaf646 MK |
481 | (typically by calling |
482 | .BR pthread_exit (3)). | |
fea681da | 483 | |
b902fe18 MK |
484 | Permission to dereference or read |
485 | .RB ( readlink (2)) | |
486 | this symbolic link is governed by a ptrace access mode | |
487 | .B PTRACE_MODE_READ_FSCREDS | |
488 | check; see | |
489 | .BR ptrace (2). | |
490 | ||
eb9a0b2f | 491 | Under Linux 2.0 and earlier, |
69119dc7 | 492 | .I /proc/[pid]/exe |
c13182ef MK |
493 | is a pointer to the binary which was executed, |
494 | and appears as a symbolic link. | |
495 | A | |
fea681da MK |
496 | .BR readlink (2) |
497 | call on this file under Linux 2.0 returns a string in the format: | |
498 | ||
59a40ed7 | 499 | [device]:inode |
fea681da MK |
500 | |
501 | For example, [0301]:1502 would be inode 1502 on device major 03 (IDE, | |
502 | MFM, etc. drives) minor 01 (first partition on the first drive). | |
503 | ||
504 | .BR find (1) | |
59a40ed7 MK |
505 | with the |
506 | .I \-inum | |
507 | option can be used to locate the file. | |
fea681da | 508 | .TP |
d4529654 | 509 | .I /proc/[pid]/fd/ |
fea681da MK |
510 | This is a subdirectory containing one entry for each file which the |
511 | process has open, named by its file descriptor, and which is a | |
c13182ef | 512 | symbolic link to the actual file. |
f78ed33a | 513 | Thus, 0 is standard input, 1 standard output, 2 standard error, and so on. |
fea681da | 514 | |
f75715e0 MK |
515 | For file descriptors for pipes and sockets, |
516 | the entries will be symbolic links whose content is the | |
517 | file type with the inode. | |
d4529654 MF |
518 | A |
519 | .BR readlink (2) | |
520 | call on this file returns a string in the format: | |
f75715e0 | 521 | |
d4529654 | 522 | type:[inode] |
f75715e0 MK |
523 | |
524 | For example, | |
525 | .I socket:[2248868] | |
526 | will be a socket and its inode is 2248868. | |
527 | For sockets, that inode can be used to find more information | |
528 | in one of the files under | |
d4529654 MF |
529 | .IR /proc/net/ . |
530 | ||
2b7a2ac5 MK |
531 | For file descriptors that have no corresponding inode |
532 | (e.g., file descriptors produced by | |
533 | .BR epoll_create (2), | |
534 | .BR eventfd (2), | |
535 | .BR inotify_init (2), | |
536 | .BR signalfd (2), | |
537 | and | |
538 | .BR timerfd (2)), | |
539 | the entry will be a symbolic link with contents of the form | |
540 | ||
541 | anon_inode:<file-type> | |
542 | ||
543 | In some cases, the | |
544 | .I file-type | |
545 | is surrounded by square brackets. | |
546 | ||
547 | For example, an epoll file descriptor will have a symbolic link | |
548 | whose content is the string | |
549 | .IR "anon_inode:[eventpoll]" . | |
550 | ||
d4529654 | 551 | .\"The following was still true as at kernel 2.6.13 |
afcaf646 | 552 | In a multithreaded process, the contents of this directory |
c13182ef | 553 | are not available if the main thread has already terminated |
afcaf646 MK |
554 | (typically by calling |
555 | .BR pthread_exit (3)). | |
556 | ||
59a40ed7 MK |
557 | Programs that will take a filename as a command-line argument, |
558 | but will not take input from standard input if no argument is supplied, | |
559 | or that write to a file named as a command-line argument, | |
560 | but will not send their output to standard output | |
561 | if no argument is supplied, can nevertheless be made to use | |
562 | standard input or standard out using | |
69119dc7 | 563 | .IR /proc/[pid]/fd . |
59a40ed7 MK |
564 | For example, assuming that |
565 | .I \-i | |
566 | is the flag designating an input file and | |
567 | .I \-o | |
568 | is the flag designating an output file: | |
a08ea57c | 569 | .in +4n |
fea681da MK |
570 | .nf |
571 | ||
b43a3b30 | 572 | .RB "$" " foobar \-i /proc/self/fd/0 \-o /proc/self/fd/1 ..." |
fea681da | 573 | .fi |
a08ea57c MK |
574 | .in |
575 | ||
fea681da MK |
576 | and you have a working filter. |
577 | .\" The following is not true in my tests (MTK): | |
578 | .\" Note that this will not work for | |
579 | .\" programs that seek on their files, as the files in the fd directory | |
580 | .\" are not seekable. | |
581 | ||
59a40ed7 MK |
582 | .I /proc/self/fd/N |
583 | is approximately the same as | |
584 | .I /dev/fd/N | |
008f1ecc | 585 | in some UNIX and UNIX-like systems. |
c13182ef | 586 | Most Linux MAKEDEV scripts symbolically link |
59a40ed7 MK |
587 | .I /dev/fd |
588 | to | |
589 | .IR /proc/self/fd , | |
590 | in fact. | |
591 | ||
592 | Most systems provide symbolic links | |
593 | .IR /dev/stdin , | |
594 | .IR /dev/stdout , | |
595 | and | |
596 | .IR /dev/stderr , | |
597 | which respectively link to the files | |
598 | .IR 0 , | |
599 | .IR 1 , | |
600 | and | |
601 | .IR 2 | |
602 | in | |
603 | .IR /proc/self/fd . | |
604 | Thus the example command above could be written as: | |
605 | .in +4n | |
606 | .nf | |
607 | ||
b43a3b30 | 608 | .RB "$" " foobar \-i /dev/stdin \-o /dev/stdout ..." |
59a40ed7 MK |
609 | .fi |
610 | .in | |
138a191e MK |
611 | .IP |
612 | Permission to dereference or read | |
613 | .RB ( readlink (2)) | |
614 | the symbolic links in this directory is governed by a ptrace access mode | |
615 | .B PTRACE_MODE_READ_FSCREDS | |
616 | check; see | |
617 | .BR ptrace (2). | |
69ab425e MK |
618 | .\" FIXME Describe /proc/[pid]/loginuid |
619 | .\" Added in 2.6.11; updating requires CAP_AUDIT_CONTROL | |
620 | .\" CONFIG_AUDITSYSCALL | |
621 | .TP | |
7e07d950 | 622 | .IR /proc/[pid]/fdinfo/ " (since Linux 2.6.22)" |
69ab425e MK |
623 | This is a subdirectory containing one entry for each file which the |
624 | process has open, named by its file descriptor. | |
0275956d | 625 | The files in this directory are readable only by the owner of the process. |
69ab425e | 626 | The contents of each file can be read to obtain information |
0275956d MK |
627 | about the corresponding file descriptor. |
628 | The content depends on the type of file referred to by the | |
d9cb0d7d | 629 | corresponding file descriptor. |
0275956d MK |
630 | |
631 | For regular files and directories, we see something like: | |
69ab425e MK |
632 | .in +4n |
633 | .nf | |
634 | ||
635 | .RB "$" " cat /proc/12015/fdinfo/4" | |
636 | pos: 1000 | |
637 | flags: 01002002 | |
0275956d | 638 | mnt_id: 21 |
69ab425e MK |
639 | .fi |
640 | .in | |
641 | ||
9599cbb3 MK |
642 | The fields are as follows: |
643 | .RS | |
644 | .TP | |
69ab425e | 645 | .I pos |
9599cbb3 MK |
646 | This is a decimal number showing the file offset. |
647 | .TP | |
69ab425e | 648 | .I flags |
9599cbb3 | 649 | This is an octal number that displays the |
69ab425e MK |
650 | file access mode and file status flags (see |
651 | .BR open (2)). | |
d7e537ce MK |
652 | If the close-on-exec file descriptor flag is set, then |
653 | .I flags | |
654 | will also include the value | |
655 | .BR O_CLOEXEC . | |
656 | ||
657 | Before Linux 3.1, | |
658 | .\" commit 1117f72ea0217ba0cc19f05adbbd8b9a397f5ab7 | |
659 | this field incorrectly displayed the setting of | |
660 | .B O_CLOEXEC | |
661 | at the time the file was opened, | |
662 | rather than the current setting of the close-on-exec flag. | |
9599cbb3 MK |
663 | .TP |
664 | .I | |
0275956d | 665 | .I mnt_id |
9599cbb3 | 666 | This field, present since Linux 3.15, |
0275956d MK |
667 | .\" commit 49d063cb353265c3af701bab215ac438ca7df36d |
668 | is the ID of the mount point containing this file. | |
669 | See the description of | |
670 | .IR /proc/[pid]/mountinfo . | |
9599cbb3 MK |
671 | .RE |
672 | .IP | |
6e7622ee MK |
673 | For eventfd file descriptors (see |
674 | .BR eventfd (2)), | |
b6a7fd50 MK |
675 | we see (since Linux 3.8) |
676 | .\" commit cbac5542d48127b546a23d816380a7926eee1c25 | |
677 | the following fields: | |
6e7622ee MK |
678 | |
679 | .in +4n | |
680 | .nf | |
681 | pos: 0 | |
682 | flags: 02 | |
683 | mnt_id: 10 | |
684 | eventfd-count: 40 | |
685 | .fi | |
686 | .in | |
687 | ||
688 | .I eventfd-count | |
689 | is the current value of the eventfd counter, in hexadecimal. | |
690 | ||
58d375dd MK |
691 | For epoll file descriptors (see |
692 | .BR epoll (7)), | |
b6a7fd50 MK |
693 | we see (since Linux 3.8) |
694 | .\" commit 138d22b58696c506799f8de759804083ff9effae | |
695 | the following fields: | |
58d375dd MK |
696 | |
697 | .in +4n | |
698 | .nf | |
699 | pos: 0 | |
700 | flags: 02 | |
701 | mnt_id: 10 | |
702 | tfd: 9 events: 19 data: 74253d2500000009 | |
703 | tfd: 7 events: 19 data: 74253d2500000007 | |
704 | .fi | |
705 | .in | |
706 | ||
707 | Each of the lines beginning | |
708 | .I tfd | |
709 | describes one of the file descriptors being monitored via | |
710 | the epoll file descriptor (see | |
711 | .BR epoll_ctl (2) | |
712 | for some details). | |
713 | The | |
714 | .IR tfd | |
715 | field is the number of the file descriptor. | |
716 | The | |
717 | .I events | |
718 | field is a hexadecimal mask of the events being monitored for this file | |
719 | descriptor. | |
720 | The | |
721 | .I data | |
722 | field is the data value associated with this file descriptor. | |
723 | ||
f8a14cac MK |
724 | For signalfd file descriptors (see |
725 | .BR signalfd (2)), | |
b6a7fd50 MK |
726 | we see (since Linux 3.8) |
727 | .\" commit 138d22b58696c506799f8de759804083ff9effae | |
728 | the following fields: | |
f8a14cac MK |
729 | |
730 | .in +4n | |
731 | .nf | |
732 | pos: 0 | |
733 | flags: 02 | |
734 | mnt_id: 10 | |
735 | sigmask: 0000000000000006 | |
736 | .fi | |
737 | .in | |
738 | ||
739 | .I sigmask | |
740 | is the hexadecimal mask of signals that are accepted via this | |
741 | signalfd file descriptor. | |
742 | (In this example, bits 2 and 3 are set, corresponding to the signals | |
743 | .B SIGINT | |
744 | and | |
745 | .BR SIGQUIT ; | |
746 | see | |
747 | .BR signal (7).) | |
4e77145c MK |
748 | |
749 | For inotify file descriptors (see | |
750 | .BR inotify (7)), | |
751 | we see (since Linux 3.8) | |
752 | the following fields: | |
753 | ||
754 | .in +4n | |
755 | .nf | |
756 | pos: 0 | |
757 | flags: 00 | |
758 | mnt_id: 11 | |
759 | inotify wd:2 ino:7ef82a sdev:800001 mask:800afff ignored_mask:0 fhandle-bytes:8 fhandle-type:1 f_handle:2af87e00220ffd73 | |
760 | inotify wd:1 ino:192627 sdev:800001 mask:800afff ignored_mask:0 fhandle-bytes:8 fhandle-type:1 f_handle:27261900802dfd73 | |
761 | .fi | |
762 | .in | |
763 | ||
764 | Each of the lines beginning with "inotify" displays information about | |
765 | one file or directory that is being monitored. | |
766 | The fields in this line are as follows: | |
767 | .RS | |
768 | .TP | |
769 | .I wd | |
770 | A watch descriptor number (in decimal). | |
771 | .TP | |
772 | .I ino | |
773 | The inode number of the target file (in hexadecimal). | |
774 | .TP | |
775 | .I sdev | |
776 | The ID of the device where the target file resides (in hexadecimal). | |
777 | .TP | |
778 | .I mask | |
779 | The mask of events being monitored for the target file (in hexadecimal). | |
780 | .RE | |
781 | .IP | |
782 | If the kernel was built with exportfs support, the path to the target | |
783 | file is exposed as a file handle, via three hexadecimal fields: | |
784 | .IR fhandle-bytes , | |
785 | .IR fhandle-type , | |
786 | and | |
787 | .IR f_handle . | |
e2444bcb MK |
788 | |
789 | For fanotify file descriptors (see | |
790 | .BR fanotify (7)), | |
791 | we see (since Linux 3.8) | |
792 | the following fields: | |
793 | ||
794 | .in +4n | |
795 | .nf | |
796 | pos: 0 | |
797 | flags: 02 | |
798 | mnt_id: 11 | |
799 | fanotify flags:0 event-flags:88002 | |
800 | fanotify ino:19264f sdev:800001 mflags:0 mask:1 ignored_mask:0 fhandle-bytes:8 fhandle-type:1 f_handle:4f261900a82dfd73 | |
801 | .fi | |
802 | .in | |
803 | ||
804 | The fourth line displays information defined when the fanotify group | |
805 | was created via | |
806 | .BR fanotify_init (2): | |
807 | .RS | |
808 | .TP | |
809 | .I flags | |
810 | The | |
811 | .I flags | |
812 | argument given to | |
813 | .BR fanotify_init (2) | |
814 | (expressed in hexadecimal). | |
815 | .TP | |
816 | .I event-flags | |
817 | The | |
818 | .I event_f_flags | |
819 | argument given to | |
820 | .BR fanotify_init (2) | |
821 | (expressed in hexadecimal). | |
822 | .RE | |
823 | .IP | |
824 | Each additional line shown in the file contains information | |
825 | about one of the marks in the fanotify group. | |
826 | Most of these fields are as for inotify, except: | |
827 | .RS | |
828 | .TP | |
829 | .I mflags | |
830 | The flags associated with the mark | |
831 | (expressed in hexadecimal). | |
832 | .TP | |
833 | .I mask | |
834 | The events mask for this mark | |
835 | (expressed in hexadecimal). | |
836 | .TP | |
837 | .I ignored_mask | |
838 | The mask of events that are ignored for this mark | |
839 | (expressed in hexadecimal). | |
840 | .RE | |
841 | .IP | |
842 | For details on these fields, see | |
843 | .BR fanotify_mark (2). | |
0ca2fc4d PS |
844 | .TP |
845 | .IR /proc/[pid]/io " (since kernel 2.6.20)" | |
68f11066 MK |
846 | .\" commit 7c3ab7381e79dfc7db14a67c6f4f3285664e1ec2 |
847 | This file contains I/O statistics for the process, for example: | |
0ca2fc4d PS |
848 | .in +4n |
849 | .nf | |
850 | ||
851 | .RB "#" " cat /proc/3828/io" | |
852 | rchar: 323934931 | |
853 | wchar: 323929600 | |
854 | syscr: 632687 | |
855 | syscw: 632675 | |
856 | read_bytes: 0 | |
857 | write_bytes: 323932160 | |
858 | cancelled_write_bytes: 0 | |
859 | .fi | |
860 | .in | |
861 | ||
862 | The fields are as follows: | |
863 | .RS | |
68f11066 MK |
864 | .TP |
865 | .IR rchar ": characters read" | |
0ca2fc4d PS |
866 | The number of bytes which this task has caused to be read from storage. |
867 | This is simply the sum of bytes which this process passed to | |
868 | .BR read (2) | |
68f11066 | 869 | and similar system calls. |
11256884 | 870 | It includes things such as terminal I/O and |
68f11066 MK |
871 | is unaffected by whether or not actual |
872 | physical disk I/O was required (the read might have been satisfied from | |
0ca2fc4d | 873 | pagecache). |
68f11066 MK |
874 | .TP |
875 | .IR wchar ": characters written" | |
0ca2fc4d PS |
876 | The number of bytes which this task has caused, or shall cause to be written |
877 | to disk. | |
878 | Similar caveats apply here as with | |
879 | .IR rchar . | |
68f11066 MK |
880 | .TP |
881 | .IR syscr ": read syscalls" | |
882 | Attempt to count the number of read I/O operations\(emthat is, | |
883 | system calls such as | |
0ca2fc4d PS |
884 | .BR read (2) |
885 | and | |
886 | .BR pread (2). | |
68f11066 MK |
887 | .TP |
888 | .IR syscw ": write syscalls" | |
889 | Attempt to count the number of write I/O operations\(emthat is, | |
890 | system calls such as | |
0ca2fc4d PS |
891 | .BR write (2) |
892 | and | |
893 | .BR pwrite (2). | |
68f11066 MK |
894 | .TP |
895 | .IR read_bytes ": bytes read" | |
0ca2fc4d PS |
896 | Attempt to count the number of bytes which this process really did cause to |
897 | be fetched from the storage layer. | |
898 | This is accurate for block-backed filesystems. | |
68f11066 MK |
899 | .TP |
900 | .IR write_bytes ": bytes written" | |
0ca2fc4d PS |
901 | Attempt to count the number of bytes which this process caused to be sent to |
902 | the storage layer. | |
68f11066 | 903 | .TP |
0ca2fc4d | 904 | .IR cancelled_write_bytes : |
0ca2fc4d PS |
905 | The big inaccuracy here is truncate. |
906 | If a process writes 1MB to a file and then deletes the file, | |
907 | it will in fact perform no writeout. | |
908 | But it will have been accounted as having caused 1MB of write. | |
68f11066 | 909 | In other words: this field represents the number of bytes which this process |
0ca2fc4d | 910 | caused to not happen, by truncating pagecache. |
68f11066 | 911 | A task can cause "negative" I/O too. |
0ca2fc4d | 912 | If this task truncates some dirty pagecache, |
68f11066 MK |
913 | some I/O which another task has been accounted for |
914 | (in its | |
915 | .IR write_bytes ) | |
916 | will not be happening. | |
917 | .RE | |
0ca2fc4d PS |
918 | .IP |
919 | .IR Note : | |
68f11066 | 920 | In the current implementation, things are a bit racy on 32-bit systems: |
0ca2fc4d PS |
921 | if process A reads process B's |
922 | .I /proc/[pid]/io | |
68f11066 | 923 | while process B is updating one of these 64-bit counters, |
0ca2fc4d | 924 | process A could see an intermediate result. |
d8e2972a MK |
925 | |
926 | Permission to access this file is governed by a ptrace access mode | |
927 | .B PTRACE_MODE_READ_FSCREDS | |
928 | check; see | |
929 | .BR ptrace (2). | |
f6e17121 | 930 | .TP |
ccdc8958 | 931 | .IR /proc/[pid]/gid_map " (since Linux 3.5)" |
d06a6170 MK |
932 | See |
933 | .BR user_namespaces (7). | |
69ab425e | 934 | .TP |
7e07d950 | 935 | .IR /proc/[pid]/limits " (since Linux 2.6.24)" |
69ab425e MK |
936 | This file displays the soft limit, hard limit, and units of measurement |
937 | for each of the process's resource limits (see | |
938 | .BR getrlimit (2)). | |
939 | Up to and including Linux 2.6.35, | |
940 | this file is protected to allow reading only by the real UID of the process. | |
941 | Since Linux 2.6.36, | |
942 | .\" commit 3036e7b490bf7878c6dae952eec5fb87b1106589 | |
943 | this file is readable by all users on the system. | |
b4f89985 PE |
944 | .TP |
945 | .IR /proc/[pid]/map_files/ " (since kernel 3.3) | |
18cdd0ac MK |
946 | .\" commit 640708a2cff7f81e246243b0073c66e6ece7e53e |
947 | This subdirectory contains entries corresponding to memory-mapped | |
b4f89985 PE |
948 | files (see |
949 | .BR mmap (2)). | |
18cdd0ac MK |
950 | Entries are named by memory region start and end |
951 | address pair (expressed as hexadecimal numbers), | |
952 | and are symbolic links to the mapped files themselves. | |
953 | Here is an example, with the output wrapped and reformatted to fit on an 80-column display: | |
b4f89985 PE |
954 | .in +4n |
955 | .nf | |
956 | ||
f2aa4dcc | 957 | .RB "#" " ls -l /proc/self/map_files/" |
18cdd0ac MK |
958 | lr\-\-\-\-\-\-\-\-. 1 root root 64 Apr 16 21:31 |
959 | 3252e00000\-3252e20000 \-> /usr/lib64/ld-2.15.so | |
b4f89985 PE |
960 | \&... |
961 | .fi | |
962 | .in | |
963 | ||
964 | Although these entries are present for memory regions that were | |
d6a56978 | 965 | mapped with the |
b4f89985 | 966 | .BR MAP_FILE |
18cdd0ac | 967 | flag, the way anonymous shared memory (regions created with the |
b4f89985 PE |
968 | .B MAP_ANON | MAP_SHARED |
969 | flags) | |
970 | is implemented in Linux | |
18cdd0ac MK |
971 | means that such regions also appear on this directory. |
972 | Here is an example where the target file is the deleted | |
973 | .I /dev/zero | |
974 | one: | |
b4f89985 PE |
975 | .in +4n |
976 | .nf | |
977 | ||
18cdd0ac MK |
978 | lrw\-\-\-\-\-\-\-. 1 root root 64 Apr 16 21:33 |
979 | 7fc075d2f000\-7fc075e6f000 \-> /dev/zero (deleted) | |
b4f89985 PE |
980 | .fi |
981 | .in | |
982 | ||
983 | This directory appears only if the | |
984 | .B CONFIG_CHECKPOINT_RESTORE | |
985 | kernel configuration option is enabled. | |
f2aa4dcc MK |
986 | Privilege |
987 | .RB ( CAP_SYS_ADMIN ) | |
988 | .\" FIXME | |
989 | .\" This may change. See the mail thread | |
990 | .\" [RFC][PATCH v2] procfs: Always expose /proc/<pid>/map_files/ and make it readable | |
991 | .\" from Jan 2015 | |
992 | is required to view the contents of this directory. | |
fea681da | 993 | .TP |
69119dc7 | 994 | .I /proc/[pid]/maps |
fea681da MK |
995 | A file containing the currently mapped memory regions and their access |
996 | permissions. | |
bbf9f397 MK |
997 | See |
998 | .BR mmap (2) | |
999 | for some further information about memory mappings. | |
fea681da | 1000 | |
aee2f0bf MK |
1001 | Permission to access this file is governed by a ptrace access mode |
1002 | .B PTRACE_MODE_READ_FSCREDS | |
1003 | check; see | |
1004 | .BR ptrace (2). | |
1005 | ||
dd0c3b96 | 1006 | The format of the file is: |
fea681da | 1007 | |
21781757 | 1008 | .in -7n |
fea681da MK |
1009 | .nf |
1010 | .ft CW | |
fea681da | 1011 | .ft |
21781757 MK |
1012 | .I "address perms offset dev inode pathname" |
1013 | 00400000-00452000 r-xp 00000000 08:02 173521 /usr/bin/dbus-daemon | |
1014 | 00651000-00652000 r--p 00051000 08:02 173521 /usr/bin/dbus-daemon | |
1015 | 00652000-00655000 rw-p 00052000 08:02 173521 /usr/bin/dbus-daemon | |
1016 | 00e03000-00e24000 rw-p 00000000 00:00 0 [heap] | |
1017 | 00e24000-011f7000 rw-p 00000000 00:00 0 [heap] | |
182090db | 1018 | \&... |
21781757 MK |
1019 | 35b1800000-35b1820000 r-xp 00000000 08:02 135522 /usr/lib64/ld-2.15.so |
1020 | 35b1a1f000-35b1a20000 r--p 0001f000 08:02 135522 /usr/lib64/ld-2.15.so | |
1021 | 35b1a20000-35b1a21000 rw-p 00020000 08:02 135522 /usr/lib64/ld-2.15.so | |
7d2e6d74 | 1022 | 35b1a21000-35b1a22000 rw-p 00000000 00:00 0 |
21781757 MK |
1023 | 35b1c00000-35b1dac000 r-xp 00000000 08:02 135870 /usr/lib64/libc-2.15.so |
1024 | 35b1dac000-35b1fac000 ---p 001ac000 08:02 135870 /usr/lib64/libc-2.15.so | |
1025 | 35b1fac000-35b1fb0000 r--p 001ac000 08:02 135870 /usr/lib64/libc-2.15.so | |
1026 | 35b1fb0000-35b1fb2000 rw-p 001b0000 08:02 135870 /usr/lib64/libc-2.15.so | |
182090db | 1027 | \&... |
21781757 | 1028 | f2c6ff8c000-7f2c7078c000 rw-p 00000000 00:00 0 [stack:986] |
182090db | 1029 | \&... |
21781757 MK |
1030 | 7fffb2c0d000-7fffb2c2e000 rw-p 00000000 00:00 0 [stack] |
1031 | 7fffb2d48000-7fffb2d49000 r-xp 00000000 00:00 0 [vdso] | |
fea681da | 1032 | .fi |
21781757 | 1033 | .in |
fea681da | 1034 | |
7d2e6d74 | 1035 | The |
3eb8c588 MK |
1036 | .I address |
1037 | field is the address space in the process that the mapping occupies. | |
1038 | The | |
1039 | .I perms | |
1040 | field is a set of permissions: | |
fea681da MK |
1041 | |
1042 | .nf | |
1043 | .in +5 | |
1044 | r = read | |
1045 | w = write | |
1046 | x = execute | |
1047 | s = shared | |
1048 | p = private (copy on write) | |
1049 | .fi | |
1050 | .in | |
1051 | ||
3eb8c588 MK |
1052 | The |
1053 | .I offset | |
b844cf04 | 1054 | field is the offset into the file/whatever; |
3eb8c588 MK |
1055 | .I dev |
1056 | is the device | |
dd0c3b96 | 1057 | (major:minor); |
3eb8c588 MK |
1058 | .I inode |
1059 | is the inode on that device. | |
59a40ed7 | 1060 | 0 indicates that no inode is associated with the memory region, |
16e64bae | 1061 | as would be the case with BSS (uninitialized data). |
fea681da | 1062 | |
3eb8c588 MK |
1063 | The |
1064 | .I pathname | |
1065 | field will usually be the file that is backing the mapping. | |
491ea6f1 | 1066 | For ELF files, |
3eb8c588 MK |
1067 | you can easily coordinate with the |
1068 | .I offset | |
1069 | field by looking at the | |
491ea6f1 MK |
1070 | Offset field in the ELF program headers |
1071 | .RI ( "readelf\ \-l" ). | |
37d32c38 | 1072 | |
491ea6f1 | 1073 | There are additional helpful pseudo-paths: |
61b0b1f4 MK |
1074 | .RS 12 |
1075 | .TP | |
1076 | .IR [stack] | |
16e64bae | 1077 | The initial process's (also known as the main thread's) stack. |
61b0b1f4 | 1078 | .TP |
3eb8c588 | 1079 | .IR [stack:<tid>] " (since Linux 3.4)" |
a60894c5 | 1080 | .\" commit b76437579d1344b612cf1851ae610c636cec7db0 |
61b0b1f4 | 1081 | A thread's stack (where the |
3eb8c588 | 1082 | .IR <tid> |
61b0b1f4 | 1083 | is a thread ID). |
491ea6f1 | 1084 | It corresponds to the |
3eb8c588 | 1085 | .IR /proc/[pid]/task/[tid]/ |
37d32c38 | 1086 | path. |
61b0b1f4 | 1087 | .TP |
7d2e6d74 | 1088 | .IR [vdso] |
61b0b1f4 MK |
1089 | The virtual dynamically linked shared object. |
1090 | .TP | |
7d2e6d74 | 1091 | .IR [heap] |
61b0b1f4 MK |
1092 | The process's heap. |
1093 | .in | |
61b0b1f4 MK |
1094 | .RE |
1095 | .IP | |
3eb8c588 MK |
1096 | If the |
1097 | .I pathname | |
1098 | field is blank, | |
491ea6f1 | 1099 | this is an anonymous mapping as obtained via the |
37d32c38 | 1100 | .BR mmap (2) |
491ea6f1 | 1101 | function. |
61b0b1f4 MK |
1102 | There is no easy way to coordinate this back to a process's source, |
1103 | short of running it through | |
491ea6f1 MK |
1104 | .BR gdb (1), |
1105 | .BR strace (1), | |
1106 | or similar. | |
37d32c38 | 1107 | |
eb9a0b2f | 1108 | Under Linux 2.0, there is no field giving pathname. |
fea681da | 1109 | .TP |
69119dc7 | 1110 | .I /proc/[pid]/mem |
fea681da MK |
1111 | This file can be used to access the pages of a process's memory through |
1112 | .BR open (2), | |
1113 | .BR read (2), | |
1114 | and | |
ccb2bb0d | 1115 | .BR lseek (2). |
aee2f0bf MK |
1116 | |
1117 | Permission to access this file is governed by a ptrace access mode | |
1118 | .B PTRACE_MODE_ATTACH_FSCREDS | |
1119 | check; see | |
1120 | .BR ptrace (2). | |
b4e9ee8f | 1121 | .TP |
69119dc7 | 1122 | .IR /proc/[pid]/mountinfo " (since Linux 2.6.26)" |
b4e9ee8f | 1123 | .\" This info adapted from Documentation/filesystems/proc.txt |
fb4bdaa1 | 1124 | .\" commit 2d4d4864ac08caff5c204a752bd004eed4f08760 |
ef5b47f6 MK |
1125 | This file contains information about mount points |
1126 | in the process's mount namespace (see | |
1127 | .BR mount_namespaces (7)). | |
fb4bdaa1 MK |
1128 | It supplies various information |
1129 | (e.g., propagation state, root of mount for bind mounts, | |
1130 | identifier for each mount and its parent) that is missing from the (older) | |
1131 | .IR /proc/[pid]/mounts | |
1132 | file, and fixes various other problems with that file | |
1133 | (e.g., nonextensibility, | |
1134 | failure to distinguish per-mount versus per-superblock options). | |
1135 | ||
1136 | The file contains lines of the form: | |
b4e9ee8f MK |
1137 | .nf |
1138 | .ft CW | |
b4e9ee8f | 1139 | |
0f619d1f | 1140 | 36 35 98:0 /mnt1 /mnt2 rw,noatime master:1 \- ext3 /dev/root rw,errors=continue |
b4e9ee8f | 1141 | (1)(2)(3) (4) (5) (6) (7) (8) (9) (10) (11) |
b4e9ee8f MK |
1142 | .ft |
1143 | .fi | |
1144 | .IP | |
1145 | The numbers in parentheses are labels for the descriptions below: | |
3bc960c2 | 1146 | .RS 7 |
b4e9ee8f MK |
1147 | .TP 5 |
1148 | (1) | |
0f619d1f | 1149 | mount ID: a unique ID for the mount (may be reused after |
b4e9ee8f MK |
1150 | .BR umount (2)). |
1151 | .TP | |
1152 | (2) | |
0f619d1f MK |
1153 | parent ID: the ID of the parent mount |
1154 | (or of self for the top of the mount tree). | |
b4e9ee8f MK |
1155 | .TP |
1156 | (3) | |
0f619d1f | 1157 | major:minor: the value of |
b4e9ee8f | 1158 | .I st_dev |
0f619d1f | 1159 | for files on this filesystem (see |
b4e9ee8f MK |
1160 | .BR stat (2)). |
1161 | .TP | |
1162 | (4) | |
0f619d1f | 1163 | root: the pathname of the directory in the filesystem |
8d857fcb | 1164 | which forms the root of this mount. |
b4e9ee8f MK |
1165 | .TP |
1166 | (5) | |
ebdc66e2 | 1167 | mount point: the pathname of the mount point relative |
0f619d1f | 1168 | to the process's root directory. |
b4e9ee8f MK |
1169 | .TP |
1170 | (6) | |
1171 | mount options: per-mount options. | |
1172 | .TP | |
1173 | (7) | |
0f619d1f | 1174 | optional fields: zero or more fields of the form "tag[:value]"; see below. |
b4e9ee8f MK |
1175 | .TP |
1176 | (8) | |
0f619d1f | 1177 | separator: the end of the optional fields is marked by a single hyphen. |
b4e9ee8f MK |
1178 | .TP |
1179 | (9) | |
0f619d1f | 1180 | filesystem type: the filesystem type in the form "type[.subtype]". |
b4e9ee8f MK |
1181 | .TP |
1182 | (10) | |
9ee4a2b6 | 1183 | mount source: filesystem-specific information or "none". |
b4e9ee8f MK |
1184 | .TP |
1185 | (11) | |
68d86eac | 1186 | super options: per-superblock options. |
b4e9ee8f MK |
1187 | .RE |
1188 | .IP | |
966b5839 MK |
1189 | Currently, the possible optional fields are |
1190 | .IR shared , | |
1191 | .IR master , | |
1192 | .IR propagate_from , | |
1193 | and | |
1194 | .IR unbindable . | |
1195 | See | |
1196 | .BR mount_namespaces (7) | |
1197 | for a description of these fields. | |
0f619d1f MK |
1198 | Parsers should ignore all unrecognized optional fields. |
1199 | .IP | |
b4e9ee8f MK |
1200 | For more information on mount propagation see: |
1201 | .I Documentation/filesystems/sharedsubtree.txt | |
66a9882e | 1202 | in the Linux kernel source tree. |
b4e9ee8f | 1203 | .TP |
cea61382 | 1204 | .IR /proc/[pid]/mounts " (since Linux 2.4.19)" |
226cb3a8 | 1205 | This file lists all the filesystems currently mounted in the |
ef5b47f6 MK |
1206 | process's mount namespace (see |
1207 | .BR mount_namespaces (7)). | |
cea61382 MK |
1208 | The format of this file is documented in |
1209 | .BR fstab (5). | |
226cb3a8 | 1210 | |
cea61382 MK |
1211 | Since kernel version 2.6.15, this file is pollable: |
1212 | after opening the file for reading, a change in this file | |
9ee4a2b6 | 1213 | (i.e., a filesystem mount or unmount) causes |
cea61382 | 1214 | .BR select (2) |
226cb3a8 | 1215 | to mark the file descriptor as having an exceptional condition, and |
cea61382 MK |
1216 | .BR poll (2) |
1217 | and | |
1218 | .BR epoll_wait (2) | |
226cb3a8 MK |
1219 | mark the file as having a priority event |
1220 | .RB ( POLLPRI ). | |
1221 | (Before Linux 2.6.30, | |
1222 | a change in this file was indicated by the file descriptor | |
1223 | being marked as readable for | |
1224 | .BR select (2), | |
1225 | and being marked as having an error condition for | |
1226 | .BR poll (2) | |
1227 | and | |
1228 | .BR epoll_wait (2).) | |
cea61382 | 1229 | .TP |
69119dc7 | 1230 | .IR /proc/[pid]/mountstats " (since Linux 2.6.17)" |
783a6233 | 1231 | This file exports information (statistics, configuration information) |
ef5b47f6 MK |
1232 | about the mount points in the process's mount namespace (see |
1233 | .BR mount_namespaces (7)). | |
b4e9ee8f MK |
1234 | Lines in this file have the form: |
1235 | .nf | |
1236 | ||
1237 | device /dev/sda7 mounted on /home with fstype ext3 [statistics] | |
1238 | ( 1 ) ( 2 ) (3 ) (4) | |
1239 | .fi | |
1240 | .IP | |
1241 | The fields in each line are: | |
3bc960c2 | 1242 | .RS 7 |
b4e9ee8f MK |
1243 | .TP 5 |
1244 | (1) | |
1245 | The name of the mounted device | |
1246 | (or "nodevice" if there is no corresponding device). | |
1247 | .TP | |
1248 | (2) | |
9ee4a2b6 | 1249 | The mount point within the filesystem tree. |
b4e9ee8f MK |
1250 | .TP |
1251 | (3) | |
9ee4a2b6 | 1252 | The filesystem type. |
b4e9ee8f MK |
1253 | .TP |
1254 | (4) | |
1255 | Optional statistics and configuration information. | |
9ee4a2b6 | 1256 | Currently (as at Linux 2.6.26), only NFS filesystems export |
b4e9ee8f MK |
1257 | information via this field. |
1258 | .RE | |
1259 | .IP | |
90878f7c | 1260 | This file is readable only by the owner of the process. |
b4e9ee8f | 1261 | .TP |
9fb88bc8 MK |
1262 | .IR |
1263 | /proc/[pid]/net " (since Linux 2.6.25)" | |
1264 | See the description of | |
1265 | .IR /proc/net . | |
1266 | .TP | |
b4a185e5 | 1267 | .IR /proc/[pid]/ns/ " (since Linux 3.0)" |
2c4201f0 | 1268 | .\" See commit 6b4e306aa3dc94a0545eb9279475b1ab6209a31f |
b4a185e5 EB |
1269 | This is a subdirectory containing one entry for each namespace that |
1270 | supports being manipulated by | |
80e63655 | 1271 | .BR setns (2). |
cf8bfe6d MK |
1272 | For more information, see |
1273 | .BR namespaces (7). | |
b4a185e5 | 1274 | .TP |
69119dc7 | 1275 | .IR /proc/[pid]/numa_maps " (since Linux 2.6.14)" |
610f75cc MK |
1276 | See |
1277 | .BR numa (7). | |
7388733a | 1278 | .TP |
69119dc7 | 1279 | .IR /proc/[pid]/oom_adj " (since Linux 2.6.11)" |
b4e9ee8f | 1280 | This file can be used to adjust the score used to select which process |
0425de01 | 1281 | should be killed in an out-of-memory (OOM) situation. |
b4e9ee8f MK |
1282 | The kernel uses this value for a bit-shift operation of the process's |
1283 | .IR oom_score | |
1284 | value: | |
5b8dbfd4 MK |
1285 | valid values are in the range \-16 to +15, |
1286 | plus the special value \-17, | |
b4e9ee8f MK |
1287 | which disables OOM-killing altogether for this process. |
1288 | A positive score increases the likelihood of this | |
1289 | process being killed by the OOM-killer; | |
1290 | a negative score decreases the likelihood. | |
de8e9cc1 | 1291 | .IP |
b4e9ee8f MK |
1292 | The default value for this file is 0; |
1293 | a new process inherits its parent's | |
1294 | .I oom_adj | |
1295 | setting. | |
1296 | A process must be privileged | |
1297 | .RB ( CAP_SYS_RESOURCE ) | |
1298 | to update this file. | |
f2c8b197 MK |
1299 | .IP |
1300 | Since Linux 2.6.36, use of this file is deprecated in favor of | |
1301 | .IR /proc/[pid]/oom_score_adj . | |
b4e9ee8f | 1302 | .TP |
69119dc7 | 1303 | .IR /proc/[pid]/oom_score " (since Linux 2.6.11)" |
b4e9ee8f MK |
1304 | .\" See mm/oom_kill.c::badness() in the 2.6.25 sources |
1305 | This file displays the current score that the kernel gives to | |
1306 | this process for the purpose of selecting a process | |
1307 | for the OOM-killer. | |
1308 | A higher score means that the process is more likely to be | |
1309 | selected by the OOM-killer. | |
1310 | The basis for this score is the amount of memory used by the process, | |
1311 | with increases (+) or decreases (\-) for factors including: | |
1312 | .\" See mm/oom_kill.c::badness() in the 2.6.25 sources | |
1313 | .RS | |
1314 | .IP * 2 | |
1315 | whether the process creates a lot of children using | |
1316 | .BR fork (2) | |
1317 | (+); | |
1318 | .IP * | |
1319 | whether the process has been running a long time, | |
1320 | or has used a lot of CPU time (\-); | |
1321 | .IP * | |
1322 | whether the process has a low nice value (i.e., > 0) (+); | |
1323 | .IP * | |
1324 | whether the process is privileged (\-); and | |
1325 | .\" More precisely, if it has CAP_SYS_ADMIN or CAP_SYS_RESOURCE | |
1326 | .IP * | |
1327 | whether the process is making direct hardware access (\-). | |
1328 | .\" More precisely, if it has CAP_SYS_RAWIO | |
1329 | .RE | |
1330 | .IP | |
1331 | The | |
1332 | .I oom_score | |
f2c8b197 MK |
1333 | also reflects the adjustment specified by the |
1334 | .I oom_score_adj | |
1335 | or | |
b4e9ee8f MK |
1336 | .I oom_adj |
1337 | setting for the process. | |
f2c8b197 MK |
1338 | .TP |
1339 | .IR /proc/[pid]/oom_score_adj " (since Linux 2.6.36)" | |
1340 | .\" Text taken from 3.7 Documentation/filesystems/proc.txt | |
1341 | This file can be used to adjust the badness heuristic used to select which | |
1342 | process gets killed in out-of-memory conditions. | |
1343 | ||
1344 | The badness heuristic assigns a value to each candidate task ranging from 0 | |
1345 | (never kill) to 1000 (always kill) to determine which process is targeted. | |
1346 | The units are roughly a proportion along that range of | |
1347 | allowed memory the process may allocate from, | |
1348 | based on an estimation of its current memory and swap use. | |
1349 | For example, if a task is using all allowed memory, | |
1350 | its badness score will be 1000. | |
1351 | If it is using half of its allowed memory, its score will be 500. | |
1352 | ||
1353 | There is an additional factor included in the badness score: root | |
1354 | processes are given 3% extra memory over other tasks. | |
1355 | ||
1356 | The amount of "allowed" memory depends on the context | |
0633f951 | 1357 | in which the OOM-killer was called. |
f2c8b197 MK |
1358 | If it is due to the memory assigned to the allocating task's cpuset |
1359 | being exhausted, | |
1360 | the allowed memory represents the set of mems assigned to that | |
1361 | cpuset (see | |
1362 | .BR cpuset (7)). | |
1363 | If it is due to a mempolicy's node(s) being exhausted, | |
1364 | the allowed memory represents the set of mempolicy nodes. | |
1365 | If it is due to a memory limit (or swap limit) being reached, | |
1366 | the allowed memory is that configured limit. | |
1367 | Finally, if it is due to the entire system being out of memory, the | |
1368 | allowed memory represents all allocatable resources. | |
1369 | ||
1370 | The value of | |
0633f951 | 1371 | .I oom_score_adj |
f2c8b197 MK |
1372 | is added to the badness score before it |
1373 | is used to determine which task to kill. | |
1374 | Acceptable values range from \-1000 | |
1375 | (OOM_SCORE_ADJ_MIN) to +1000 (OOM_SCORE_ADJ_MAX). | |
0633f951 | 1376 | This allows user space to control the preference for OOM-killing, |
f2c8b197 | 1377 | ranging from always preferring a certain |
f082ada4 | 1378 | task or completely disabling it from OOM killing. |
f2c8b197 | 1379 | The lowest possible value, \-1000, is |
0633f951 | 1380 | equivalent to disabling OOM-killing entirely for that task, |
f2c8b197 MK |
1381 | since it will always report a badness score of 0. |
1382 | ||
1383 | Consequently, it is very simple for user space to define | |
1384 | the amount of memory to consider for each task. | |
1385 | Setting a | |
1386 | .I oom_score_adj | |
1387 | value of +500, for example, | |
1388 | is roughly equivalent to allowing the remainder of tasks sharing the | |
1389 | same system, cpuset, mempolicy, or memory controller resources | |
1390 | to use at least 50% more memory. | |
1391 | A value of \-500, on the other hand, would be roughly | |
1392 | equivalent to discounting 50% of the task's | |
1393 | allowed memory from being considered as scoring against the task. | |
1394 | ||
0633f951 | 1395 | For backward compatibility with previous kernels, |
f2c8b197 MK |
1396 | .I /proc/[pid]/oom_adj |
1397 | can still be used to tune the badness score. | |
1398 | Its value is | |
9f1b9726 | 1399 | scaled linearly with |
f2c8b197 MK |
1400 | .IR oom_score_adj . |
1401 | ||
1402 | Writing to | |
1403 | .IR /proc/[pid]/oom_score_adj | |
1404 | or | |
1405 | .IR /proc/[pid]/oom_adj | |
1406 | will change the other with its scaled value. | |
b0aa1e51 MK |
1407 | .TP |
1408 | .IR /proc/[pid]/pagemap " (since Linux 2.6.25)" | |
1409 | This file shows the mapping of each of the process's virtual pages | |
1410 | into physical page frames or swap area. | |
1411 | It contains one 64-bit value for each virtual page, | |
1412 | with the bits set as follows: | |
1413 | .RS 12 | |
1414 | .TP | |
1415 | 63 | |
1416 | If set, the page is present in RAM. | |
1417 | .TP | |
1418 | 62 | |
1419 | If set, the page is in swap space | |
1420 | .TP | |
1421 | 61 (since Linux 3.5) | |
1422 | The page is a file-mapped page or a shared anonymous page. | |
1423 | .TP | |
1424 | 60-56 (since Linux 3.11) | |
1425 | Zero | |
1426 | .\" Not quite true; see commit 541c237c0923f567c9c4cabb8a81635baadc713f | |
1427 | .TP | |
1428 | 55 (Since Linux 3.11) | |
1429 | PTE is soft-dirty | |
1430 | (see the kernel source file | |
1431 | .IR Documentation/vm/soft-dirty.txt ). | |
1432 | .TP | |
1433 | 54-0 | |
1434 | If the page is present in RAM (bit 63), then these bits | |
1435 | provide the page frame number, which can be used to index | |
1436 | .IR /proc/kpageflags | |
1437 | and | |
1438 | .IR /proc/kpagecount . | |
1439 | If the page is present in swap (bit 62), | |
1440 | then bits 4-0 give the swap type, and bits 54-5 encode the swap offset. | |
1441 | .RE | |
1442 | .IP | |
1443 | Before Linux 3.11, bits 60-55 were | |
1444 | used to encode the base-2 log of the page size. | |
1445 | .IP | |
1446 | To employ | |
1447 | .IR /proc/[pid]/pagemap | |
1448 | efficiently, use | |
1449 | .IR /proc/[pid]/maps | |
1450 | to determine which areas of memory are actually mapped and seek | |
1451 | to skip over unmapped regions. | |
1452 | .IP | |
1453 | The | |
1454 | .IR /proc/[pid]/pagemap | |
1455 | file is present only if the | |
1456 | .B CONFIG_PROC_PAGE_MONITOR | |
1457 | kernel configuration option is enabled. | |
aee2f0bf MK |
1458 | |
1459 | Permission to access this file is governed by a ptrace access mode | |
1460 | .B PTRACE_MODE_READ_FSCREDS | |
1461 | check; see | |
1462 | .BR ptrace (2). | |
7c2905d1 MK |
1463 | .TP |
1464 | .IR /proc/[pid]/personality " (since Linux 2.6.28)" | |
1465 | .\" commit 478307230810d7e2a753ed220db9066dfdf88718 | |
1466 | This read-only file exposes the process's execution domain, as set by | |
1467 | .BR personality (2). | |
1468 | The value is displayed in hexadecimal notation. | |
4834ae91 MK |
1469 | |
1470 | Permission to access this file is governed by a ptrace access mode | |
1471 | .B PTRACE_MODE_ATTACH_FSCREDS | |
1472 | check; see | |
1473 | .BR ptrace (2). | |
fea681da | 1474 | .TP |
69119dc7 | 1475 | .I /proc/[pid]/root |
008f1ecc | 1476 | UNIX and Linux support the idea of a per-process root of the |
9ee4a2b6 | 1477 | filesystem, set by the |
fea681da | 1478 | .BR chroot (2) |
c13182ef MK |
1479 | system call. |
1480 | This file is a symbolic link that points to the process's | |
14d70713 MK |
1481 | root directory, and behaves in the same way as |
1482 | .IR exe , | |
1483 | and | |
1484 | .IR fd/* . | |
afcaf646 MK |
1485 | |
1486 | .\" The following was still true as at kernel 2.6.13 | |
c13182ef MK |
1487 | In a multithreaded process, the contents of this symbolic link |
1488 | are not available if the main thread has already terminated | |
afcaf646 MK |
1489 | (typically by calling |
1490 | .BR pthread_exit (3)). | |
b902fe18 MK |
1491 | |
1492 | Permission to dereference or read | |
1493 | .RB ( readlink (2)) | |
1494 | this symbolic link is governed by a ptrace access mode | |
1495 | .B PTRACE_MODE_READ_FSCREDS | |
1496 | check; see | |
1497 | .BR ptrace (2). | |
f34f0182 MK |
1498 | .\" FIXME Describe /proc/[pid]/projid_map |
1499 | .\" Added in 3.7, commit f76d207a66c3a53defea67e7d36c3eb1b7d6d61d | |
69119dc7 | 1500 | .\" FIXME Describe /proc/[pid]/seccomp |
6aefb6df | 1501 | .\" Added in 2.6.12 |
bea08fec | 1502 | .\" |
69119dc7 | 1503 | .\" FIXME Describe /proc/[pid]/sessionid |
b4e9ee8f | 1504 | .\" Added in 2.6.25; read-only; only readable by real UID |
b3fb99e8 | 1505 | .\" commit 1e0bd7550ea9cf474b1ad4c6ff5729a507f75fdc |
b4e9ee8f | 1506 | .\" CONFIG_AUDITSYSCALL |
bea08fec | 1507 | .\" |
69119dc7 | 1508 | .\" FIXME Describe /proc/[pid]/sched |
b4e9ee8f MK |
1509 | .\" Added in 2.6.23 |
1510 | .\" CONFIG_SCHED_DEBUG, and additional fields if CONFIG_SCHEDSTATS | |
1511 | .\" Displays various scheduling parameters | |
1512 | .\" This file can be written, to reset stats | |
ef4f4031 | 1513 | .\" The set of fields exposed by this file have changed |
b3fb99e8 MK |
1514 | .\" significantly over time. |
1515 | .\" commit 43ae34cb4cd650d1eb4460a8253a8e747ba052ac | |
1516 | .\" | |
69119dc7 MK |
1517 | .\" FIXME Describe /proc/[pid]/schedstats and |
1518 | .\" /proc/[pid]/task/[tid]/schedstats | |
b4e9ee8f MK |
1519 | .\" Added in 2.6.9 |
1520 | .\" CONFIG_SCHEDSTATS | |
fea681da | 1521 | .TP |
51dea63a MK |
1522 | .IR /proc/[pid]/seccomp " (from Linux 2.6.12 to 2.6.22)" |
1523 | Read/set the seccomp mode for the process. | |
1524 | If this file contains the value zero, seccomp mode is not enabled. | |
1525 | Writing the value 1 to this file (irreversibly) places the process in | |
1526 | seccomp mode: the only permitted system calls are | |
1527 | .BR read (2), | |
1528 | .BR write (2), | |
1529 | .BR _exit (2), | |
1530 | and | |
1531 | .BR sigreturn (2). | |
1532 | This file went away in Linux 2.6.23, | |
1533 | .\" commit 1d9d02feeee89e9132034d504c9a45eeaf618a3d | |
1534 | when it was replaced by a | |
1535 | .BR prctl (2)-based | |
1536 | mechanism. | |
1537 | .TP | |
5c92b1b7 | 1538 | .IR /proc/[pid]/setgroups " (since Linux 3.19)" |
ab28dba9 MK |
1539 | See |
1540 | .BR user_namespaces (7). | |
d520465b | 1541 | .TP |
69119dc7 | 1542 | .IR /proc/[pid]/smaps " (since Linux 2.6.14)" |
b07b19c4 | 1543 | This file shows memory consumption for each of the process's mappings. |
859503c3 MK |
1544 | (The |
1545 | .BR pmap (1) | |
1546 | command displays similar information, | |
1547 | in a form that may be easier for parsing.) | |
1f0add28 | 1548 | For each mapping there is a series of lines such as the following: |
a08ea57c | 1549 | .in +4n |
b07b19c4 MK |
1550 | .nf |
1551 | ||
1f0add28 | 1552 | 00400000-0048a000 r-xp 00000000 fd:03 960637 /bin/bash |
95fe794d PG |
1553 | Size: 552 kB |
1554 | Rss: 460 kB | |
1555 | Pss: 100 kB | |
1556 | Shared_Clean: 452 kB | |
1557 | Shared_Dirty: 0 kB | |
1558 | Private_Clean: 8 kB | |
1559 | Private_Dirty: 0 kB | |
1560 | Referenced: 460 kB | |
1561 | Anonymous: 0 kB | |
1562 | AnonHugePages: 0 kB | |
1563 | Swap: 0 kB | |
1564 | KernelPageSize: 4 kB | |
1565 | MMUPageSize: 4 kB | |
1566 | Locked: 0 kB | |
b07b19c4 MK |
1567 | |
1568 | .fi | |
a08ea57c | 1569 | .in |
b07b19c4 MK |
1570 | The first of these lines shows the same information as is displayed |
1571 | for the mapping in | |
69119dc7 | 1572 | .IR /proc/[pid]/maps . |
b07b19c4 | 1573 | The remaining lines show the size of the mapping, |
95fe794d PG |
1574 | the amount of the mapping that is currently resident in RAM ("Rss"), |
1575 | the process' proportional share of this mapping ("Pss"), | |
1f0add28 | 1576 | the number of clean and dirty shared pages in the mapping, |
c7ce200d | 1577 | and the number of clean and dirty private pages in the mapping. |
95fe794d | 1578 | "Referenced" indicates the amount of memory currently marked as |
1f0add28 MK |
1579 | referenced or accessed. |
1580 | "Anonymous" shows the amount of memory | |
1581 | that does not belong to any file. | |
1582 | "Swap" shows how much | |
95fe794d PG |
1583 | would-be-anonymous memory is also used, but out on swap. |
1584 | ||
d6a56978 | 1585 | The "KernelPageSize" entry is the page size used by the kernel to back a VMA. |
1f0add28 MK |
1586 | This matches the size used by the MMU in the majority of cases. |
1587 | However, one counter-example occurs on PPC64 kernels | |
1588 | whereby a kernel using 64K as a base page size may still use 4K | |
1589 | pages for the MMU on older processors. | |
1590 | To distinguish, this | |
1591 | patch reports "MMUPageSize" as the page size used by the MMU. | |
95fe794d PG |
1592 | |
1593 | The "Locked" indicates whether the mapping is locked in memory | |
1594 | or not. | |
1595 | ||
1596 | "VmFlags" field represents the kernel flags associated with | |
1f0add28 MK |
1597 | the particular virtual memory area in two letter encoded manner. |
1598 | The codes are the following: | |
1599 | ||
95fe794d | 1600 | rd - readable |
1f0add28 | 1601 | wr - writable |
95fe794d PG |
1602 | ex - executable |
1603 | sh - shared | |
1604 | mr - may read | |
1605 | mw - may write | |
1606 | me - may execute | |
1607 | ms - may share | |
723e333c | 1608 | gd - stack segment grows down |
95fe794d PG |
1609 | pf - pure PFN range |
1610 | dw - disabled write to the mapped file | |
1611 | lo - pages are locked in memory | |
1612 | io - memory mapped I/O area | |
1613 | sr - sequential read advise provided | |
1614 | rr - random read advise provided | |
1615 | dc - do not copy area on fork | |
1616 | de - do not expand area on remapping | |
1617 | ac - area is accountable | |
1618 | nr - swap space is not reserved for the area | |
1619 | ht - area uses huge tlb pages | |
1620 | nl - non-linear mapping | |
1621 | ar - architecture specific flag | |
1622 | dd - do not include area into core dump | |
1623 | sd - soft-dirty flag | |
1624 | mm - mixed map area | |
1625 | hg - huge page advise flag | |
1626 | nh - no-huge page advise flag | |
b5408a0f | 1627 | mg - mergeable advise flag |
b07b19c4 | 1628 | |
e618d945 MK |
1629 | The |
1630 | .IR /proc/[pid]/smaps | |
1631 | file is present only if the | |
1632 | .B CONFIG_PROC_PAGE_MONITOR | |
1633 | kernel configuration option is enabled. | |
b07b19c4 | 1634 | .TP |
67aac6fb MK |
1635 | .IR /proc/[pid]/stack " (since Linux 2.6.29)" |
1636 | .\" 2ec220e27f5040aec1e88901c1b6ea3d135787ad | |
1637 | This file provides a symbolic trace of the function calls in this | |
1638 | process's kernel stack. | |
1639 | This file is provided only if the kernel was built with the | |
1640 | .B CONFIG_STACKTRACE | |
1641 | configuration option. | |
4834ae91 MK |
1642 | |
1643 | Permission to access this file is governed by a ptrace access mode | |
1644 | .B PTRACE_MODE_ATTACH_FSCREDS | |
1645 | check; see | |
1646 | .BR ptrace (2). | |
67aac6fb | 1647 | .TP |
69119dc7 | 1648 | .I /proc/[pid]/stat |
c13182ef MK |
1649 | Status information about the process. |
1650 | This is used by | |
1651 | .BR ps (1). | |
082bf5b8 MK |
1652 | It is defined in the kernel source file |
1653 | .IR fs/proc/array.c "." | |
fea681da MK |
1654 | |
1655 | The fields, in order, with their proper | |
1656 | .BR scanf (3) | |
b02b4b74 MK |
1657 | format specifiers, are listed below. |
1658 | Whether or not certain of these fields display valid information is governed by | |
1659 | a ptrace access mode | |
1660 | .BR PTRACE_MODE_READ_FSCREDS "\ |\ " PTRACE_MODE_NOAUDIT | |
1661 | check (refer to | |
1662 | .BR ptrace (2)). | |
1663 | If the check denies access, then the field value is displayed as 0. | |
1664 | The affected fields are indicated with the marking [PT]. | |
1665 | ||
fea681da | 1666 | .RS |
62e4a418 MK |
1667 | .TP 10 |
1668 | (1) \fIpid\fP \ %d | |
1669 | .br | |
1670 | The process ID. | |
fea681da | 1671 | .TP |
62e4a418 MK |
1672 | (2) \fIcomm\fP \ %s |
1673 | The filename of the executable, in parentheses. | |
c13182ef | 1674 | This is visible whether or not the executable is swapped out. |
fea681da | 1675 | .TP |
62e4a418 | 1676 | (3) \fIstate\fP \ %c |
31293f37 MK |
1677 | One of the following characters, indicating process state: |
1678 | .RS | |
1679 | .IP R 3 | |
1680 | Running | |
1681 | .IP S | |
1682 | Sleeping in an interruptible wait | |
1683 | .IP D | |
1684 | Waiting in uninterruptible | |
1685 | disk sleep | |
1686 | .IP Z | |
1687 | Zombie | |
1688 | .IP T | |
1689 | Stopped (on a signal) or (before Linux 2.6.33) trace stopped | |
1690 | .IP t | |
1691 | .\" commit 44d90df6b757c59651ddd55f1a84f28132b50d29 | |
1692 | Tracing stop (Linux 2.6.33 onward) | |
1693 | .IP W | |
1694 | Paging (only before Linux 2.6.0) | |
1695 | .IP X | |
ef4f4031 | 1696 | Dead (from Linux 2.6.0 onward) |
31293f37 MK |
1697 | .IP x |
1698 | .\" commit 44d90df6b757c59651ddd55f1a84f28132b50d29 | |
1699 | Dead (Linux 2.6.33 to | |
1700 | .\" commit 74e37200de8e9c4e09b70c21c3f13c2071e77457 | |
1701 | 3.13 only) | |
1702 | .IP K | |
1703 | .\" commit 44d90df6b757c59651ddd55f1a84f28132b50d29 | |
1704 | Wakekill (Linux 2.6.33 to | |
1705 | .\" commit 74e37200de8e9c4e09b70c21c3f13c2071e77457 | |
1706 | 3.13 only) | |
1707 | .IP W | |
1708 | .\" commit 44d90df6b757c59651ddd55f1a84f28132b50d29 | |
1709 | Waking (Linux 2.6.33 to | |
1710 | .\" commit 74e37200de8e9c4e09b70c21c3f13c2071e77457 | |
1711 | 3.13 only) | |
1712 | .IP P | |
1713 | .\" commit f2530dc71cf0822f90bb63ea4600caaef33a66bb | |
1714 | Parked (Linux 3.9 to | |
1715 | .\" commit 74e37200de8e9c4e09b70c21c3f13c2071e77457 | |
1716 | 3.13 only) | |
1717 | .RE | |
fea681da | 1718 | .TP |
62e4a418 | 1719 | (4) \fIppid\fP \ %d |
e0fdc57c | 1720 | The PID of the parent of this process. |
fea681da | 1721 | .TP |
62e4a418 MK |
1722 | (5) \fIpgrp\fP \ %d |
1723 | The process group ID of the process. | |
fea681da | 1724 | .TP |
62e4a418 MK |
1725 | (6) \fIsession\fP \ %d |
1726 | The session ID of the process. | |
fea681da | 1727 | .TP |
62e4a418 MK |
1728 | (7) \fItty_nr\fP \ %d |
1729 | The controlling terminal of the process. | |
59a40ed7 MK |
1730 | (The minor device number is contained in the combination of bits |
1731 | 31 to 20 and 7 to 0; | |
b97deb97 | 1732 | the major device number is in bits 15 to 8.) |
fea681da | 1733 | .TP |
62e4a418 | 1734 | (8) \fItpgid\fP \ %d |
fea681da | 1735 | .\" This field and following, up to and including wchan added 0.99.1 |
62e4a418 | 1736 | The ID of the foreground process group of the controlling |
59a40ed7 | 1737 | terminal of the process. |
fea681da | 1738 | .TP |
62e4a418 MK |
1739 | (9) \fIflags\fP \ %u |
1740 | The kernel flags word of the process. | |
c13182ef | 1741 | For bit meanings, |
66a9882e | 1742 | see the PF_* defines in the Linux kernel source file |
00702acc | 1743 | .IR include/linux/sched.h . |
fea681da | 1744 | Details depend on the kernel version. |
62e4a418 MK |
1745 | |
1746 | The format for this field was %lu before Linux 2.6. | |
fea681da | 1747 | .TP |
ee566744 | 1748 | (10) \fIminflt\fP \ %lu |
62e4a418 | 1749 | The number of minor faults the process has made which have not |
fea681da MK |
1750 | required loading a memory page from disk. |
1751 | .TP | |
62e4a418 MK |
1752 | (11) \fIcminflt\fP \ %lu |
1753 | The number of minor faults that the process's | |
fea681da MK |
1754 | waited-for children have made. |
1755 | .TP | |
62e4a418 MK |
1756 | (12) \fImajflt\fP \ %lu |
1757 | The number of major faults the process has made which have | |
fea681da MK |
1758 | required loading a memory page from disk. |
1759 | .TP | |
62e4a418 MK |
1760 | (13) \fIcmajflt\fP \ %lu |
1761 | The number of major faults that the process's | |
fea681da MK |
1762 | waited-for children have made. |
1763 | .TP | |
62e4a418 MK |
1764 | (14) \fIutime\fP \ %lu |
1765 | Amount of time that this process has been scheduled in user mode, | |
7a017e24 | 1766 | measured in clock ticks (divide by |
67914165 | 1767 | .IR sysconf(_SC_CLK_TCK) ). |
a1c9dc59 MK |
1768 | This includes guest time, \fIguest_time\fP |
1769 | (time spent running a virtual CPU, see below), | |
1770 | so that applications that are not aware of the guest time field | |
1771 | do not lose that time from their calculations. | |
fea681da | 1772 | .TP |
62e4a418 MK |
1773 | (15) \fIstime\fP \ %lu |
1774 | Amount of time that this process has been scheduled in kernel mode, | |
7a017e24 | 1775 | measured in clock ticks (divide by |
67914165 | 1776 | .IR sysconf(_SC_CLK_TCK) ). |
fea681da | 1777 | .TP |
62e4a418 MK |
1778 | (16) \fIcutime\fP \ %ld |
1779 | Amount of time that this process's | |
7a017e24 MK |
1780 | waited-for children have been scheduled in user mode, |
1781 | measured in clock ticks (divide by | |
67914165 | 1782 | .IR sysconf(_SC_CLK_TCK) ). |
c13182ef | 1783 | (See also |
fea681da | 1784 | .BR times (2).) |
a1c9dc59 MK |
1785 | This includes guest time, \fIcguest_time\fP |
1786 | (time spent running a virtual CPU, see below). | |
fea681da | 1787 | .TP |
62e4a418 MK |
1788 | (17) \fIcstime\fP \ %ld |
1789 | Amount of time that this process's | |
7a017e24 MK |
1790 | waited-for children have been scheduled in kernel mode, |
1791 | measured in clock ticks (divide by | |
67914165 | 1792 | .IR sysconf(_SC_CLK_TCK) ). |
fea681da | 1793 | .TP |
62e4a418 MK |
1794 | (18) \fIpriority\fP \ %ld |
1795 | (Explanation for Linux 2.6) | |
59a40ed7 MK |
1796 | For processes running a real-time scheduling policy |
1797 | .RI ( policy | |
1798 | below; see | |
1799 | .BR sched_setscheduler (2)), | |
1800 | this is the negated scheduling priority, minus one; | |
1801 | that is, a number in the range \-2 to \-100, | |
1802 | corresponding to real-time priorities 1 to 99. | |
1803 | For processes running under a non-real-time scheduling policy, | |
1804 | this is the raw nice value | |
1805 | .RB ( setpriority (2)) | |
1806 | as represented in the kernel. | |
1807 | The kernel stores nice values as numbers | |
1808 | in the range 0 (high) to 39 (low), | |
1809 | corresponding to the user-visible nice range of \-20 to 19. | |
1810 | ||
1811 | Before Linux 2.6, this was a scaled value based on | |
1812 | the scheduler weighting given to this process. | |
1813 | .\" And back in kernel 1.2 days things were different again. | |
fea681da | 1814 | .TP |
62e4a418 MK |
1815 | (19) \fInice\fP \ %ld |
1816 | The nice value (see | |
59a40ed7 MK |
1817 | .BR setpriority (2)), |
1818 | a value in the range 19 (low priority) to \-20 (high priority). | |
1819 | .\" Back in kernel 1.2 days things were different. | |
fea681da MK |
1820 | .\" .TP |
1821 | .\" \fIcounter\fP %ld | |
1822 | .\" The current maximum size in jiffies of the process's next timeslice, | |
1823 | .\" or what is currently left of its current timeslice, if it is the | |
1824 | .\" currently running process. | |
1825 | .\" .TP | |
1826 | .\" \fItimeout\fP %u | |
1827 | .\" The time in jiffies of the process's next timeout. | |
0e94f77b | 1828 | .\" timeout was removed sometime around 2.1/2.2 |
aa610245 | 1829 | .TP |
62e4a418 MK |
1830 | (20) \fInum_threads\fP \ %ld |
1831 | Number of threads in this process (since Linux 2.6). | |
bb83d1b9 | 1832 | Before kernel 2.6, this field was hard coded to 0 as a placeholder |
0e94f77b | 1833 | for an earlier removed field. |
fea681da | 1834 | .TP |
62e4a418 MK |
1835 | (21) \fIitrealvalue\fP \ %ld |
1836 | The time in jiffies before the next | |
8bd58774 MK |
1837 | .B SIGALRM |
1838 | is sent to the process due to an interval timer. | |
0e94f77b MK |
1839 | Since kernel 2.6.17, this field is no longer maintained, |
1840 | and is hard coded as 0. | |
fea681da | 1841 | .TP |
62e4a418 MK |
1842 | (22) \fIstarttime\fP \ %llu |
1843 | The time the process started after system boot. | |
055024ed MK |
1844 | In kernels before Linux 2.6, this value was expressed in jiffies. |
1845 | Since Linux 2.6, the value is expressed in clock ticks (divide by | |
1846 | .IR sysconf(_SC_CLK_TCK) ). | |
62e4a418 MK |
1847 | |
1848 | The format for this field was %lu before Linux 2.6. | |
fea681da | 1849 | .TP |
62e4a418 MK |
1850 | (23) \fIvsize\fP \ %lu |
1851 | Virtual memory size in bytes. | |
fea681da | 1852 | .TP |
62e4a418 MK |
1853 | (24) \fIrss\fP \ %ld |
1854 | Resident Set Size: number of pages the process has in real memory. | |
c13182ef | 1855 | This is just the pages which |
5fab2e7c | 1856 | count toward text, data, or stack space. |
c13182ef | 1857 | This does not include pages |
fea681da MK |
1858 | which have not been demand-loaded in, or which are swapped out. |
1859 | .TP | |
62e4a418 MK |
1860 | (25) \fIrsslim\fP \ %lu |
1861 | Current soft limit in bytes on the rss of the process; | |
59a40ed7 MK |
1862 | see the description of |
1863 | .B RLIMIT_RSS | |
1864 | in | |
2b5407af | 1865 | .BR getrlimit (2). |
fea681da | 1866 | .TP |
b02b4b74 | 1867 | (26) \fIstartcode\fP \ %lu \ [PT] |
62e4a418 | 1868 | The address above which program text can run. |
fea681da | 1869 | .TP |
b02b4b74 | 1870 | (27) \fIendcode\fP \ %lu \ [PT] |
62e4a418 | 1871 | The address below which program text can run. |
fea681da | 1872 | .TP |
b02b4b74 | 1873 | (28) \fIstartstack\fP \ %lu \ [PT] |
62e4a418 | 1874 | The address of the start (i.e., bottom) of the stack. |
fea681da | 1875 | .TP |
b02b4b74 | 1876 | (29) \fIkstkesp\fP \ %lu \ [PT] |
62e4a418 | 1877 | The current value of ESP (stack pointer), as found in the |
fea681da MK |
1878 | kernel stack page for the process. |
1879 | .TP | |
b02b4b74 | 1880 | (30) \fIkstkeip\fP \ %lu \ [PT] |
62e4a418 | 1881 | The current EIP (instruction pointer). |
fea681da | 1882 | .TP |
62e4a418 MK |
1883 | (31) \fIsignal\fP \ %lu |
1884 | The bitmap of pending signals, displayed as a decimal number. | |
59a40ed7 | 1885 | Obsolete, because it does not provide information on real-time signals; use |
69119dc7 | 1886 | .I /proc/[pid]/status |
59a40ed7 | 1887 | instead. |
fea681da | 1888 | .TP |
62e4a418 MK |
1889 | (32) \fIblocked\fP \ %lu |
1890 | The bitmap of blocked signals, displayed as a decimal number. | |
59a40ed7 | 1891 | Obsolete, because it does not provide information on real-time signals; use |
69119dc7 | 1892 | .I /proc/[pid]/status |
59a40ed7 | 1893 | instead. |
fea681da | 1894 | .TP |
62e4a418 MK |
1895 | (33) \fIsigignore\fP \ %lu |
1896 | The bitmap of ignored signals, displayed as a decimal number. | |
59a40ed7 | 1897 | Obsolete, because it does not provide information on real-time signals; use |
69119dc7 | 1898 | .I /proc/[pid]/status |
59a40ed7 | 1899 | instead. |
fea681da | 1900 | .TP |
62e4a418 MK |
1901 | (34) \fIsigcatch\fP \ %lu |
1902 | The bitmap of caught signals, displayed as a decimal number. | |
59a40ed7 | 1903 | Obsolete, because it does not provide information on real-time signals; use |
69119dc7 | 1904 | .I /proc/[pid]/status |
59a40ed7 | 1905 | instead. |
fea681da | 1906 | .TP |
b02b4b74 | 1907 | (35) \fIwchan\fP \ %lu \ [PT] |
62e4a418 | 1908 | This is the "channel" in which the process is waiting. |
2054f761 MK |
1909 | It is the address of a location in the kernel where the process is sleeping. |
1910 | The corresponding symbolic name can be found in | |
1911 | .IR /proc/[pid]/wchan . | |
fea681da | 1912 | .TP |
62e4a418 | 1913 | (36) \fInswap\fP \ %lu |
0633f951 | 1914 | .\" nswap was added in 2.0 |
4d9b6984 | 1915 | Number of pages swapped (not maintained). |
fea681da | 1916 | .TP |
62e4a418 | 1917 | (37) \fIcnswap\fP \ %lu |
0633f951 | 1918 | .\" cnswap was added in 2.0 |
4d9b6984 | 1919 | Cumulative \fInswap\fP for child processes (not maintained). |
fea681da | 1920 | .TP |
62e4a418 MK |
1921 | (38) \fIexit_signal\fP \ %d \ (since Linux 2.1.22) |
1922 | Signal to be sent to parent when we die. | |
fea681da | 1923 | .TP |
62e4a418 MK |
1924 | (39) \fIprocessor\fP \ %d \ (since Linux 2.2.8) |
1925 | CPU number last executed on. | |
568105c6 | 1926 | .TP |
62e4a418 MK |
1927 | (40) \fIrt_priority\fP \ %u \ (since Linux 2.5.19) |
1928 | Real-time scheduling priority, a number in the range 1 to 99 for | |
59a40ed7 MK |
1929 | processes scheduled under a real-time policy, |
1930 | or 0, for non-real-time processes (see | |
568105c6 MK |
1931 | .BR sched_setscheduler (2)). |
1932 | .TP | |
62e4a418 MK |
1933 | (41) \fIpolicy\fP \ %u \ (since Linux 2.5.19) |
1934 | Scheduling policy (see | |
568105c6 | 1935 | .BR sched_setscheduler (2)). |
cd60dedd | 1936 | Decode using the SCHED_* constants in |
59a40ed7 | 1937 | .IR linux/sched.h . |
62e4a418 MK |
1938 | |
1939 | The format for this field was %lu before Linux 2.6.22. | |
167450d6 | 1940 | .TP |
62e4a418 MK |
1941 | (42) \fIdelayacct_blkio_ticks\fP \ %llu \ (since Linux 2.6.18) |
1942 | Aggregated block I/O delays, measured in clock ticks (centiseconds). | |
14c06953 | 1943 | .TP |
62e4a418 MK |
1944 | (43) \fIguest_time\fP \ %lu \ (since Linux 2.6.24) |
1945 | Guest time of the process (time spent running a virtual CPU | |
7a017e24 | 1946 | for a guest operating system), measured in clock ticks (divide by |
67914165 | 1947 | .IR sysconf(_SC_CLK_TCK) ). |
14c06953 | 1948 | .TP |
62e4a418 MK |
1949 | (44) \fIcguest_time\fP \ %ld \ (since Linux 2.6.24) |
1950 | Guest time of the process's children, measured in clock ticks (divide by | |
67914165 | 1951 | .IR sysconf(_SC_CLK_TCK) ). |
fea681da | 1952 | .TP |
b02b4b74 | 1953 | (45) \fIstart_data\fP \ %lu \ (since Linux 3.3) \ [PT] |
0be30a54 | 1954 | .\" commit b3f7f573a20081910e34e99cbc91831f4f02f1ff |
62e4a418 | 1955 | Address above which program initialized and |
426bc8d7 | 1956 | uninitialized (BSS) data are placed. |
12449ae3 | 1957 | .TP |
b02b4b74 | 1958 | (46) \fIend_data\fP \ %lu \ (since Linux 3.3) \ [PT] |
0be30a54 | 1959 | .\" commit b3f7f573a20081910e34e99cbc91831f4f02f1ff |
62e4a418 | 1960 | Address below which program initialized and |
426bc8d7 | 1961 | uninitialized (BSS) data are placed. |
12449ae3 | 1962 | .TP |
b02b4b74 | 1963 | (47) \fIstart_brk\fP \ %lu \ (since Linux 3.3) \ [PT] |
0be30a54 | 1964 | .\" commit b3f7f573a20081910e34e99cbc91831f4f02f1ff |
62e4a418 | 1965 | Address above which program heap can be expanded with |
426bc8d7 | 1966 | .BR brk (2). |
12449ae3 | 1967 | .TP |
b02b4b74 | 1968 | (48) \fIarg_start\fP \ %lu \ (since Linux 3.5) \ [PT] |
0be30a54 | 1969 | .\" commit 5b172087f99189416d5f47fd7ab5e6fb762a9ba3 |
62e4a418 | 1970 | Address above which program command-line arguments |
426bc8d7 MK |
1971 | .RI ( argv ) |
1972 | are placed. | |
12449ae3 | 1973 | .TP |
b02b4b74 | 1974 | (49) \fIarg_end\fP \ %lu \ (since Linux 3.5) \ [PT] |
0be30a54 | 1975 | .\" commit 5b172087f99189416d5f47fd7ab5e6fb762a9ba3 |
62e4a418 | 1976 | Address below program command-line arguments |
426bc8d7 MK |
1977 | .RI ( argv ) |
1978 | are placed. | |
12449ae3 | 1979 | .TP |
b02b4b74 | 1980 | (50) \fIenv_start\fP \ %lu \ (since Linux 3.5) \ [PT] |
0be30a54 | 1981 | .\" commit 5b172087f99189416d5f47fd7ab5e6fb762a9ba3 |
62e4a418 | 1982 | Address above which program environment is placed. |
12449ae3 | 1983 | .TP |
b02b4b74 | 1984 | (51) \fIenv_end\fP \ %lu \ (since Linux 3.5) \ [PT] |
0be30a54 | 1985 | .\" commit 5b172087f99189416d5f47fd7ab5e6fb762a9ba3 |
62e4a418 | 1986 | Address below which program environment is placed. |
12449ae3 | 1987 | .TP |
b02b4b74 | 1988 | (52) \fIexit_code\fP \ %d \ (since Linux 3.5) \ [PT] |
0be30a54 | 1989 | .\" commit 5b172087f99189416d5f47fd7ab5e6fb762a9ba3 |
62e4a418 | 1990 | The thread's exit status in the form reported by |
426bc8d7 | 1991 | .BR waitpid (2). |
12449ae3 | 1992 | .RE |
1993 | .TP | |
69119dc7 | 1994 | .I /proc/[pid]/statm |
59a40ed7 | 1995 | Provides information about memory usage, measured in pages. |
c13182ef | 1996 | The columns are: |
a08ea57c MK |
1997 | .in +4n |
1998 | .nf | |
1999 | ||
cb42fb56 | 2000 | size (1) total program size |
69119dc7 | 2001 | (same as VmSize in \fI/proc/[pid]/status\fP) |
cb42fb56 | 2002 | resident (2) resident set size |
69119dc7 | 2003 | (same as VmRSS in \fI/proc/[pid]/status\fP) |
cb42fb56 MK |
2004 | share (3) shared pages (i.e., backed by a file) |
2005 | text (4) text (code) | |
59a40ed7 | 2006 | .\" (not including libs; broken, includes data segment) |
cb42fb56 MK |
2007 | lib (5) library (unused in Linux 2.6) |
2008 | data (6) data + stack | |
59a40ed7 | 2009 | .\" (including libs; broken, includes library text) |
cb42fb56 | 2010 | dt (7) dirty pages (unused in Linux 2.6) |
a08ea57c MK |
2011 | .fi |
2012 | .in | |
fea681da | 2013 | .TP |
69119dc7 | 2014 | .I /proc/[pid]/status |
fea681da | 2015 | Provides much of the information in |
69119dc7 | 2016 | .I /proc/[pid]/stat |
fea681da | 2017 | and |
69119dc7 | 2018 | .I /proc/[pid]/statm |
fea681da | 2019 | in a format that's easier for humans to parse. |
16b5f7ba MK |
2020 | Here's an example: |
2021 | .in +4n | |
2022 | .nf | |
2023 | ||
b43a3b30 | 2024 | .RB "$" " cat /proc/$$/status" |
16b5f7ba | 2025 | Name: bash |
a79343e9 | 2026 | Umask: 0022 |
16b5f7ba | 2027 | State: S (sleeping) |
aac0b30f | 2028 | Tgid: 17248 |
2d2dfb69 | 2029 | Ngid: 0 |
aac0b30f MK |
2030 | Pid: 17248 |
2031 | PPid: 17200 | |
16b5f7ba MK |
2032 | TracerPid: 0 |
2033 | Uid: 1000 1000 1000 1000 | |
2034 | Gid: 100 100 100 100 | |
2035 | FDSize: 256 | |
2036 | Groups: 16 33 100 | |
aac0b30f MK |
2037 | NStgid: 17248 |
2038 | NSpid: 17248 | |
2039 | NSpgid: 17248 | |
2040 | NSsid: 17200 | |
16b5f7ba MK |
2041 | VmPeak: 9136 kB |
2042 | VmSize: 7896 kB | |
2043 | VmLck: 0 kB | |
15789039 | 2044 | VmPin: 0 kB |
16b5f7ba MK |
2045 | VmHWM: 7572 kB |
2046 | VmRSS: 6316 kB | |
2047 | VmData: 5224 kB | |
2048 | VmStk: 88 kB | |
2049 | VmExe: 572 kB | |
2050 | VmLib: 1708 kB | |
e28af9cd | 2051 | VmPMD: 4 kB |
16b5f7ba | 2052 | VmPTE: 20 kB |
49f6dda7 | 2053 | VmSwap: 0 kB |
16b5f7ba MK |
2054 | Threads: 1 |
2055 | SigQ: 0/3067 | |
2056 | SigPnd: 0000000000000000 | |
2057 | ShdPnd: 0000000000000000 | |
2058 | SigBlk: 0000000000010000 | |
2059 | SigIgn: 0000000000384004 | |
2060 | SigCgt: 000000004b813efb | |
2061 | CapInh: 0000000000000000 | |
2062 | CapPrm: 0000000000000000 | |
2063 | CapEff: 0000000000000000 | |
2064 | CapBnd: ffffffffffffffff | |
6112ea97 | 2065 | CapAmb: 0000000000000000 |
039b6546 | 2066 | Seccomp: 0 |
16b5f7ba MK |
2067 | Cpus_allowed: 00000001 |
2068 | Cpus_allowed_list: 0 | |
2069 | Mems_allowed: 1 | |
2070 | Mems_allowed_list: 0 | |
2071 | voluntary_ctxt_switches: 150 | |
2072 | nonvoluntary_ctxt_switches: 545 | |
2073 | .fi | |
2074 | .in | |
2075 | .IP | |
2076 | The fields are as follows: | |
2077 | .RS | |
2078 | .IP * 2 | |
2079 | .IR Name : | |
2080 | Command run by this process. | |
2081 | .IP * | |
a79343e9 MK |
2082 | .IR Umask : |
2083 | Process umask, expressed in octal with a leading zero. | |
2084 | (Since Linux 4.7.) | |
2085 | .IP * | |
16b5f7ba | 2086 | .IR State : |
4175f999 MK |
2087 | Current state of the process. |
2088 | One of | |
16b5f7ba MK |
2089 | "R (running)", |
2090 | "S (sleeping)", | |
2091 | "D (disk sleep)", | |
2092 | "T (stopped)", | |
2093 | "T (tracing stop)", | |
2094 | "Z (zombie)", | |
2095 | or | |
2096 | "X (dead)". | |
2097 | .IP * | |
2098 | .IR Tgid : | |
2099 | Thread group ID (i.e., Process ID). | |
2100 | .IP * | |
2d2dfb69 MK |
2101 | .IR Ngid : |
2102 | NUMA group ID (0 if none; since Linux 3.13). | |
2103 | .IP * | |
16b5f7ba MK |
2104 | .IR Pid : |
2105 | Thread ID (see | |
2106 | .BR gettid (2)). | |
2107 | .IP * | |
a1bc91d5 MK |
2108 | .IR PPid : |
2109 | PID of parent process. | |
2110 | .IP * | |
16b5f7ba MK |
2111 | .IR TracerPid : |
2112 | PID of process tracing this process (0 if not being traced). | |
2113 | .IP * | |
2114 | .IR Uid ", " Gid : | |
9ee4a2b6 | 2115 | Real, effective, saved set, and filesystem UIDs (GIDs). |
16b5f7ba MK |
2116 | .IP * |
2117 | .IR FDSize : | |
2118 | Number of file descriptor slots currently allocated. | |
2119 | .IP * | |
2120 | .IR Groups : | |
2121 | Supplementary group list. | |
2122 | .IP * | |
aac0b30f MK |
2123 | .I NStgid |
2124 | Thread group ID (i.e., PID) in each of the PID namespaces of which | |
2125 | .I [pid] | |
2126 | is a member. | |
2127 | The leftmost entry shows the value with respect to the PID namespace | |
2128 | of the reading process, | |
2129 | followed by the value in successively nested inner namespaces. | |
2130 | .\" commit e4bc33245124db69b74a6d853ac76c2976f472d5 | |
2131 | (Since Linux 4.1.) | |
2132 | .IP * | |
2133 | .I NSpid | |
2134 | Thread ID in each of the PID namespaces of which | |
2135 | .I [pid] | |
2136 | is a member. | |
2137 | The fields are ordered as for | |
2138 | .IR NStgid . | |
2139 | (Since Linux 4.1.) | |
2140 | .IP * | |
2141 | .I NSpgid | |
2142 | Process group ID in each of the PID namespaces of which | |
2143 | .I [pid] | |
2144 | is a member. | |
2145 | The fields are ordered as for | |
2146 | .IR NStgid . | |
2147 | (Since Linux 4.1.) | |
2148 | .IP * | |
2149 | .I NSsid | |
2150 | descendant namespace session ID hierarchy | |
2151 | Session ID in each of the PID namespaces of which | |
2152 | .I [pid] | |
2153 | is a member. | |
2154 | The fields are ordered as for | |
2155 | .IR NStgid . | |
2156 | (Since Linux 4.1.) | |
2157 | .IP * | |
16b5f7ba MK |
2158 | .IR VmPeak : |
2159 | Peak virtual memory size. | |
2160 | .IP * | |
2161 | .IR VmSize : | |
2162 | Virtual memory size. | |
2163 | .IP * | |
2164 | .IR VmLck : | |
fde39195 MK |
2165 | Locked memory size (see |
2166 | .BR mlock (3)). | |
16b5f7ba | 2167 | .IP * |
15789039 TY |
2168 | .IR VmPin : |
2169 | Pinned memory size | |
2170 | .\" commit bc3e53f682d93df677dbd5006a404722b3adfe18 | |
2171 | (since Linux 3.2). | |
2172 | These are pages that can't be moved because something needs to | |
2173 | directly access physical memory. | |
2174 | .IP * | |
16b5f7ba MK |
2175 | .IR VmHWM : |
2176 | Peak resident set size ("high water mark"). | |
2177 | .IP * | |
2178 | .IR VmRSS : | |
2179 | Resident set size. | |
2180 | .IP * | |
2181 | .IR VmData ", " VmStk ", " VmExe : | |
2182 | Size of data, stack, and text segments. | |
2183 | .IP * | |
2184 | .IR VmLib : | |
2185 | Shared library code size. | |
2186 | .IP * | |
2187 | .IR VmPTE : | |
2188 | Page table entries size (since Linux 2.6.10). | |
2189 | .IP * | |
e28af9cd MK |
2190 | .IR VmPMD : |
2191 | .\" commit dc6c9a35b66b520cf67e05d8ca60ebecad3b0479 | |
73b9cbe1 | 2192 | Size of second-level page tables (since Linux 4.0). |
e28af9cd | 2193 | .IP * |
ac4b0eb3 | 2194 | .IR VmSwap : |
1ddc1665 | 2195 | .\" commit b084d4353ff99d824d3bc5a5c2c22c70b1fba722 |
fce21149 MK |
2196 | Swapped-out virtual memory size by anonymous private pages; |
2197 | shmem swap usage is not included (since Linux 2.6.34). | |
49f6dda7 | 2198 | .IP * |
16b5f7ba MK |
2199 | .IR Threads : |
2200 | Number of threads in process containing this thread. | |
2201 | .IP * | |
6ee625eb MK |
2202 | .IR SigQ : |
2203 | This field contains two slash-separated numbers that relate to | |
2204 | queued signals for the real user ID of this process. | |
2205 | The first of these is the number of currently queued | |
2206 | signals for this real user ID, and the second is the | |
2207 | resource limit on the number of queued signals for this process | |
2208 | (see the description of | |
2209 | .BR RLIMIT_SIGPENDING | |
2210 | in | |
2211 | .BR getrlimit (2)). | |
2212 | .IP * | |
16b5f7ba MK |
2213 | .IR SigPnd ", " ShdPnd : |
2214 | Number of signals pending for thread and for process as a whole (see | |
2215 | .BR pthreads (7) | |
2216 | and | |
2217 | .BR signal (7)). | |
2218 | .IP * | |
2219 | .IR SigBlk ", " SigIgn ", " SigCgt : | |
2220 | Masks indicating signals being blocked, ignored, and caught (see | |
2221 | .BR signal (7)). | |
2222 | .IP * | |
2223 | .IR CapInh ", " CapPrm ", " CapEff : | |
2224 | Masks of capabilities enabled in inheritable, permitted, and effective sets | |
2225 | (see | |
2226 | .BR capabilities (7)). | |
2227 | .IP * | |
2228 | .IR CapBnd : | |
2229 | Capability Bounding set | |
7e07d950 | 2230 | (since Linux 2.6.26, see |
16b5f7ba MK |
2231 | .BR capabilities (7)). |
2232 | .IP * | |
6112ea97 MK |
2233 | .IR CapAmb : |
2234 | Ambient capability set | |
2235 | (since Linux 4.3, see | |
2236 | .BR capabilities (7)). | |
2237 | .IP * | |
039b6546 MK |
2238 | .IR Seccomp : |
2239 | .\" commit 2f4b3bf6b2318cfaa177ec5a802f4d8d6afbd816 | |
2240 | Seccomp mode of the process | |
2241 | (since Linux 3.8, see | |
2242 | .BR seccomp (2)). | |
2243 | 0 means | |
2244 | .BR SECCOMP_MODE_DISABLED ; | |
2245 | 1 means | |
2246 | .BR SECCOMP_MODE_STRICT ; | |
2247 | 2 means | |
2248 | .BR SECCOMP_MODE_FILTER . | |
2249 | This field is provided only if the kernel was built with the | |
2250 | .BR CONFIG_SECCOMP | |
2251 | kernel configuration option enabled. | |
2252 | .IP * | |
16b5f7ba MK |
2253 | .IR Cpus_allowed : |
2254 | Mask of CPUs on which this process may run | |
2255 | (since Linux 2.6.24, see | |
2256 | .BR cpuset (7)). | |
2257 | .IP * | |
2258 | .IR Cpus_allowed_list : | |
2259 | Same as previous, but in "list format" | |
2260 | (since Linux 2.6.26, see | |
2261 | .BR cpuset (7)). | |
2262 | .IP * | |
2263 | .IR Mems_allowed : | |
2264 | Mask of memory nodes allowed to this process | |
2265 | (since Linux 2.6.24, see | |
2266 | .BR cpuset (7)). | |
2267 | .IP * | |
2268 | .IR Mems_allowed_list : | |
2269 | Same as previous, but in "list format" | |
2270 | (since Linux 2.6.26, see | |
2271 | .BR cpuset (7)). | |
2272 | .IP * | |
7c82878a | 2273 | .IR voluntary_ctxt_switches ", " nonvoluntary_ctxt_switches : |
16b5f7ba MK |
2274 | Number of voluntary and involuntary context switches (since Linux 2.6.23). |
2275 | .RE | |
afb7b014 MK |
2276 | .TP |
2277 | .IR /proc/[pid]/syscall " (since Linux 2.6.27)" | |
2278 | .\" commit ebcb67341fee34061430f3367f2e507e52ee051b | |
2279 | This file exposes the system call number and argument registers for the | |
2280 | system call currently being executed by the process, | |
2281 | followed by the values of the stack pointer and program counter registers. | |
2282 | The values of all six argument registers are exposed, | |
2283 | although most system calls use fewer registers. | |
2284 | ||
2285 | If the process is blocked, but not in a system call, | |
1fb61947 | 2286 | then the file displays \-1 in place of the system call number, |
afb7b014 | 2287 | followed by just the values of the stack pointer and program counter. |
64fcb6e1 | 2288 | If process is not blocked, then the file contains just the string "running". |
afb7b014 MK |
2289 | |
2290 | This file is present only if the kernel was configured with | |
2291 | .BR CONFIG_HAVE_ARCH_TRACEHOOK . | |
4834ae91 MK |
2292 | |
2293 | Permission to access this file is governed by a ptrace access mode | |
2294 | .B PTRACE_MODE_ATTACH_FSCREDS | |
2295 | check; see | |
2296 | .BR ptrace (2). | |
fea681da | 2297 | .TP |
69119dc7 | 2298 | .IR /proc/[pid]/task " (since Linux 2.6.0-test6)" |
afcaf646 MK |
2299 | This is a directory that contains one subdirectory |
2300 | for each thread in the process. | |
69119dc7 MK |
2301 | The name of each subdirectory is the numerical thread ID |
2302 | .RI ( [tid] ) | |
2303 | of the thread (see | |
afcaf646 MK |
2304 | .BR gettid (2)). |
2305 | Within each of these subdirectories, there is a set of | |
2306 | files with the same names and contents as under the | |
69119dc7 | 2307 | .I /proc/[pid] |
afcaf646 MK |
2308 | directories. |
2309 | For attributes that are shared by all threads, the contents for | |
2310 | each of the files under the | |
69119dc7 | 2311 | .I task/[tid] |
afcaf646 | 2312 | subdirectories will be the same as in the corresponding |
c13182ef | 2313 | file in the parent |
69119dc7 | 2314 | .I /proc/[pid] |
afcaf646 | 2315 | directory |
c13182ef | 2316 | (e.g., in a multithreaded process, all of the |
69119dc7 | 2317 | .I task/[tid]/cwd |
c13182ef | 2318 | files will have the same value as the |
69119dc7 | 2319 | .I /proc/[pid]/cwd |
c13182ef | 2320 | file in the parent directory, since all of the threads in a process |
afcaf646 MK |
2321 | share a working directory). |
2322 | For attributes that are distinct for each thread, | |
c13182ef | 2323 | the corresponding files under |
69119dc7 | 2324 | .I task/[tid] |
afcaf646 | 2325 | may have different values (e.g., various fields in each of the |
69119dc7 | 2326 | .I task/[tid]/status |
afcaf646 MK |
2327 | files may be different for each thread). |
2328 | ||
2329 | .\" The following was still true as at kernel 2.6.13 | |
2330 | In a multithreaded process, the contents of the | |
69119dc7 | 2331 | .I /proc/[pid]/task |
c13182ef | 2332 | directory are not available if the main thread has already terminated |
afcaf646 MK |
2333 | (typically by calling |
2334 | .BR pthread_exit (3)). | |
2335 | .TP | |
1509ca0e MK |
2336 | .IR /proc/[pid]/timers " (since Linux 3.10)" |
2337 | .\" commit 5ed67f05f66c41e39880a6d61358438a25f9fee5 | |
2338 | .\" commit 48f6a7a511ef8823fdff39afee0320092d43a8a0 | |
2339 | A list of the POSIX timers for this process. | |
93691c1e | 2340 | Each timer is listed with a line that starts with the string "ID:". |
1509ca0e MK |
2341 | For example: |
2342 | ||
2343 | .in +4n | |
2344 | .nf | |
2345 | ID: 1 | |
2346 | signal: 60/00007fff86e452a8 | |
2347 | notify: signal/pid.2634 | |
2348 | ClockID: 0 | |
2349 | ID: 0 | |
2350 | signal: 60/00007fff86e452a8 | |
2351 | notify: signal/pid.2634 | |
2352 | ClockID: 1 | |
2353 | .fi | |
2354 | .in | |
2355 | ||
2356 | The lines shown for each timer have the following meanings: | |
2357 | .RS | |
2358 | .TP | |
2359 | .I ID | |
2360 | The ID for this timer. | |
2361 | This is not the same as the timer ID returned by | |
2362 | .BR timer_create (2); | |
2363 | rather, it is the same kernel-internal ID that is available via the | |
2364 | .I si_timerid | |
2365 | field of the | |
2366 | .IR siginfo_t | |
2367 | structure (see | |
2368 | .BR sigaction (2)). | |
2369 | .TP | |
2370 | .I signal | |
2371 | This is the signal number that this timer uses to deliver notifications | |
2372 | followed by a slash, and then the | |
7f1ea8fb | 2373 | .I sigev_value |
1509ca0e MK |
2374 | value supplied to the signal handler. |
2375 | Valid only for timers that notify via a signal. | |
2376 | .TP | |
2377 | .I notify | |
2378 | The part before the slash specifies the mechanism | |
2379 | that this timer uses to deliver notifications, | |
2380 | and is one of "thread", "signal", or "none". | |
2381 | Immediately following the slash is either the string "tid" for timers | |
2382 | with | |
2383 | .B SIGEV_THREAD_ID | |
2384 | notification, or "pid" for timers that notify by other mechanisms. | |
dbe6f88b MK |
2385 | Following the "." is the PID of the process |
2386 | (or the kernel thread ID of the thread) that will be delivered | |
1509ca0e MK |
2387 | a signal if the timer delivers notifications via a signal. |
2388 | .TP | |
2389 | .I ClockID | |
2390 | This field identifies the clock that the timer uses for measuring time. | |
2391 | For most clocks, this is a number that matches one of the user-space | |
2392 | .BR CLOCK_* | |
9d54c087 | 2393 | constants exposed via |
1509ca0e MK |
2394 | .IR <time.h> . |
2395 | .B CLOCK_PROCESS_CPUTIME_ID | |
2396 | timers display with a value of -6 | |
2397 | in this field. | |
2398 | .B CLOCK_THREAD_CPUTIME_ID | |
2399 | timers display with a value of -2 | |
2400 | in this field. | |
2401 | .RE | |
5734da6d MK |
2402 | .IP |
2403 | This file is available only when the kernel was configured with | |
2404 | .BR CONFIG_CHECKPOINT_RESTORE . | |
1509ca0e | 2405 | .TP |
11f60142 MK |
2406 | .IR /proc/[pid]/timerslack_ns " (since Linux 4.6)" |
2407 | .\" commit da8b44d5a9f8bf26da637b7336508ca534d6b319 | |
2408 | .\" commit 5de23d435e88996b1efe0e2cebe242074ce67c9e | |
2409 | This file exposes the process's "current" timer slack value, | |
2410 | expressed in nanoseconds. | |
2411 | The file is writable, | |
2412 | allowing the process's timer slack value to be changed. | |
2413 | Writing 0 to this file resets the "current" timer slack to the | |
2414 | "default" timer slack value. | |
2415 | For further details, see the discussion of | |
2416 | .BR PR_SET_TIMERSLACK | |
2417 | in | |
2418 | .BR prctl (2). | |
a62e0e01 MK |
2419 | |
2420 | Permission to access this file is governed by a ptrace access mode | |
2421 | .B PTRACE_MODE_ATTACH_FSCREDS | |
2422 | check; see | |
2423 | .BR ptrace (2). | |
11f60142 | 2424 | .TP |
b1aad373 MK |
2425 | .IR /proc/[pid]/uid_map ", " /proc/[pid]/gid_map " (since Linux 3.5)" |
2426 | See | |
2427 | .BR user_namespaces (7). | |
2428 | .TP | |
2429 | .IR /proc/[pid]/wchan " (since Linux 2.6.0)" | |
2430 | The symbolic name corresponding to the location | |
2431 | in the kernel where the process is sleeping. | |
82664739 MK |
2432 | |
2433 | Permission to access this file is governed by a ptrace access mode | |
2434 | .B PTRACE_MODE_READ_FSCREDS | |
2435 | check; see | |
2436 | .BR ptrace (2). | |
b1aad373 MK |
2437 | .TP |
2438 | .I /proc/apm | |
2439 | Advanced power management version and battery information when | |
2440 | .B CONFIG_APM | |
2441 | is defined at kernel compilation time. | |
2442 | .TP | |
2443 | .I /proc/buddyinfo | |
2444 | This file contains information which is used for diagnosing memory | |
2445 | fragmentation issues. | |
2446 | Each line starts with the identification of the node and the name | |
2447 | of the zone which together identify a memory region | |
2448 | This is then | |
2449 | followed by the count of available chunks of a certain order in | |
2450 | which these zones are split. | |
2451 | The size in bytes of a certain order is given by the formula: | |
2452 | ||
2453 | (2^order)\ *\ PAGE_SIZE | |
2454 | ||
2455 | The binary buddy allocator algorithm inside the kernel will split | |
2456 | one chunk into two chunks of a smaller order (thus with half the | |
2457 | size) or combine two contiguous chunks into one larger chunk of | |
2458 | a higher order (thus with double the size) to satisfy allocation | |
2459 | requests and to counter memory fragmentation. | |
2460 | The order matches the column number, when starting to count at zero. | |
2461 | ||
2462 | For example on a x86_64 system: | |
2463 | ||
2464 | .in -12n | |
2465 | .nf | |
2466 | Node 0, zone DMA 1 1 1 0 2 1 1 0 1 1 3 | |
2467 | Node 0, zone DMA32 65 47 4 81 52 28 13 10 5 1 404 | |
2468 | Node 0, zone Normal 216 55 189 101 84 38 37 27 5 3 587 | |
2469 | .fi | |
2470 | .in | |
2471 | ||
2472 | In this example, there is one node containing three zones and there | |
2473 | are 11 different chunk sizes. | |
2474 | If the page size is 4 kilobytes, then the first zone called | |
2475 | .I DMA | |
2476 | (on x86 the first 16 megabyte of memory) has 1 chunk of 4 kilobytes | |
2477 | (order 0) available and has 3 chunks of 4 megabytes (order 10) available. | |
2478 | ||
2479 | If the memory is heavily fragmented, the counters for higher | |
2480 | order chunks will be zero and allocation of large contiguous areas | |
2481 | will fail. | |
2482 | ||
2483 | Further information about the zones can be found in | |
2484 | .IR /proc/zoneinfo . | |
2485 | .TP | |
2486 | .I /proc/bus | |
2487 | Contains subdirectories for installed busses. | |
2488 | .TP | |
2489 | .I /proc/bus/pccard | |
2490 | Subdirectory for PCMCIA devices when | |
2491 | .B CONFIG_PCMCIA | |
2492 | is set at kernel compilation time. | |
2493 | .TP | |
fea681da MK |
2494 | .I /proc/bus/pccard/drivers |
2495 | .TP | |
2496 | .I /proc/bus/pci | |
c13182ef | 2497 | Contains various bus subdirectories and pseudo-files containing |
59a40ed7 | 2498 | information about PCI busses, installed devices, and device |
c13182ef MK |
2499 | drivers. |
2500 | Some of these files are not ASCII. | |
fea681da MK |
2501 | .TP |
2502 | .I /proc/bus/pci/devices | |
59a40ed7 | 2503 | Information about PCI devices. |
c13182ef | 2504 | They may be accessed through |
fea681da MK |
2505 | .BR lspci (8) |
2506 | and | |
2507 | .BR setpci (8). | |
2508 | .TP | |
12b23dfe MK |
2509 | .IR /proc/cgroups " (since Linux 2.6.24)" |
2510 | See | |
2511 | .BR cgroups (7). | |
2512 | .TP | |
fea681da | 2513 | .I /proc/cmdline |
c13182ef MK |
2514 | Arguments passed to the Linux kernel at boot time. |
2515 | Often done via a boot manager such as | |
59a40ed7 MK |
2516 | .BR lilo (8) |
2517 | or | |
2518 | .BR grub (8). | |
f6e524c4 MK |
2519 | .TP |
2520 | .IR /proc/config.gz " (since Linux 2.6)" | |
2521 | This file exposes the configuration options that were used | |
c3d9780d | 2522 | to build the currently running kernel, |
f6e524c4 MK |
2523 | in the same format as they would be shown in the |
2524 | .I .config | |
2525 | file that resulted when configuring the kernel (using | |
2526 | .IR "make xconfig" , | |
2527 | .IR "make config" , | |
2528 | or similar). | |
2529 | The file contents are compressed; view or search them using | |
f78ed33a MK |
2530 | .BR zcat (1) |
2531 | and | |
2532 | .BR zgrep (1). | |
f6e524c4 | 2533 | As long as no changes have been made to the following file, |
250e01ec MK |
2534 | the contents of |
2535 | .I /proc/config.gz | |
2536 | are the same as those provided by : | |
f6e524c4 MK |
2537 | .in +4n |
2538 | .nf | |
2539 | ||
c3074d70 | 2540 | cat /lib/modules/$(uname \-r)/build/.config |
f6e524c4 MK |
2541 | .fi |
2542 | .in | |
250e01ec MK |
2543 | .IP |
2544 | .I /proc/config.gz | |
90878f7c | 2545 | is provided only if the kernel is configured with |
250e01ec | 2546 | .BR CONFIG_IKCONFIG_PROC . |
fea681da | 2547 | .TP |
577c0e20 MK |
2548 | .I /proc/crypto |
2549 | A list of the ciphers provided by the kernel crypto API. | |
2550 | For details, see the kernel | |
2551 | .I "Linux Kernel Crypto API" | |
2552 | documentation available under the kernel source directory | |
2553 | .IR Documentation/DocBook . | |
2554 | (That documentation can be built using a command such as | |
2555 | .IR "make htmldocs" | |
2556 | in the root directory of the kernel source tree.) | |
2557 | .TP | |
fea681da MK |
2558 | .I /proc/cpuinfo |
2559 | This is a collection of CPU and system architecture dependent items, | |
2560 | for each supported architecture a different list. | |
2561 | Two common entries are \fIprocessor\fP which gives CPU number and | |
c13182ef MK |
2562 | \fIbogomips\fP; a system constant that is calculated |
2563 | during kernel initialization. | |
2564 | SMP machines have information for | |
fea681da | 2565 | each CPU. |
a091f002 MK |
2566 | The |
2567 | .BR lscpu (1) | |
2568 | command gathers its information from this file. | |
fea681da MK |
2569 | .TP |
2570 | .I /proc/devices | |
c13182ef MK |
2571 | Text listing of major numbers and device groups. |
2572 | This can be used by MAKEDEV scripts for consistency with the kernel. | |
fea681da MK |
2573 | .TP |
2574 | .IR /proc/diskstats " (since Linux 2.5.69)" | |
2575 | This file contains disk I/O statistics for each disk device. | |
66a9882e | 2576 | See the Linux kernel source file |
fea681da MK |
2577 | .I Documentation/iostats.txt |
2578 | for further information. | |
2579 | .TP | |
2580 | .I /proc/dma | |
c13182ef | 2581 | This is a list of the registered \fIISA\fP DMA (direct memory access) |
fea681da MK |
2582 | channels in use. |
2583 | .TP | |
2584 | .I /proc/driver | |
2585 | Empty subdirectory. | |
2586 | .TP | |
2587 | .I /proc/execdomains | |
2588 | List of the execution domains (ABI personalities). | |
2589 | .TP | |
2590 | .I /proc/fb | |
097585ed MK |
2591 | Frame buffer information when |
2592 | .B CONFIG_FB | |
2593 | is defined during kernel compilation. | |
fea681da MK |
2594 | .TP |
2595 | .I /proc/filesystems | |
9ee4a2b6 MK |
2596 | A text listing of the filesystems which are supported by the kernel, |
2597 | namely filesystems which were compiled into the kernel or whose kernel | |
6387216b MK |
2598 | modules are currently loaded. |
2599 | (See also | |
fb477da2 | 2600 | .BR filesystems (5).) |
9ee4a2b6 | 2601 | If a filesystem is marked with "nodev", |
809d0164 | 2602 | this means that it does not require a block device to be mounted |
9ee4a2b6 | 2603 | (e.g., virtual filesystem, network filesystem). |
809d0164 MK |
2604 | |
2605 | Incidentally, this file may be used by | |
2606 | .BR mount (8) | |
9ee4a2b6 MK |
2607 | when no filesystem is specified and it didn't manage to determine the |
2608 | filesystem type. | |
2609 | Then filesystems contained in this file are tried | |
809d0164 | 2610 | (excepted those that are marked with "nodev"). |
fea681da MK |
2611 | .TP |
2612 | .I /proc/fs | |
df352acc | 2613 | .\" FIXME Much more needs to be said about /proc/fs |
91085d85 | 2614 | .\" |
df352acc MK |
2615 | Contains subdirectories that in turn contain files |
2616 | with information about (certain) mounted filesystems. | |
fea681da MK |
2617 | .TP |
2618 | .I /proc/ide | |
2619 | This directory | |
59a40ed7 MK |
2620 | exists on systems with the IDE bus. |
2621 | There are directories for each IDE channel and attached device. | |
c13182ef | 2622 | Files include: |
fea681da | 2623 | |
a08ea57c | 2624 | .in +4n |
fea681da MK |
2625 | .nf |
2626 | cache buffer size in KB | |
2627 | capacity number of sectors | |
2628 | driver driver version | |
2629 | geometry physical and logical geometry | |
9fdfa163 | 2630 | identify in hexadecimal |
fea681da MK |
2631 | media media type |
2632 | model manufacturer's model number | |
2633 | settings drive settings | |
9fdfa163 MK |
2634 | smart_thresholds in hexadecimal |
2635 | smart_values in hexadecimal | |
fea681da | 2636 | .fi |
a08ea57c | 2637 | .in |
fea681da | 2638 | |
c13182ef | 2639 | The |
fea681da MK |
2640 | .BR hdparm (8) |
2641 | utility provides access to this information in a friendly format. | |
2642 | .TP | |
2643 | .I /proc/interrupts | |
23ec6ff0 MK |
2644 | This is used to record the number of interrupts per CPU per IO device. |
2645 | Since Linux 2.6.24, | |
2646 | for the i386 and x86_64 architectures, at least, this also includes | |
2647 | interrupts internal to the system (that is, not associated with a device | |
2648 | as such), such as NMI (nonmaskable interrupt), LOC (local timer interrupt), | |
2649 | and for SMP systems, TLB (TLB flush interrupt), RES (rescheduling | |
2650 | interrupt), CAL (remote function call interrupt), and possibly others. | |
2651 | Very easy to read formatting, done in ASCII. | |
fea681da MK |
2652 | .TP |
2653 | .I /proc/iomem | |
2654 | I/O memory map in Linux 2.4. | |
2655 | .TP | |
2656 | .I /proc/ioports | |
c13182ef | 2657 | This is a list of currently registered Input-Output port regions that |
fea681da MK |
2658 | are in use. |
2659 | .TP | |
2660 | .IR /proc/kallsyms " (since Linux 2.5.71)" | |
2661 | This holds the kernel exported symbol definitions used by the | |
2662 | .BR modules (X) | |
2663 | tools to dynamically link and bind loadable modules. | |
2664 | In Linux 2.5.47 and earlier, a similar file with slightly different syntax | |
2665 | was named | |
2666 | .IR ksyms . | |
2667 | .TP | |
2668 | .I /proc/kcore | |
2669 | This file represents the physical memory of the system and is stored | |
c13182ef MK |
2670 | in the ELF core file format. |
2671 | With this pseudo-file, and an unstripped | |
9a67332e MK |
2672 | kernel |
2673 | .RI ( /usr/src/linux/vmlinux ) | |
2674 | binary, GDB can be used to | |
fea681da MK |
2675 | examine the current state of any kernel data structures. |
2676 | ||
2677 | The total length of the file is the size of physical memory (RAM) plus | |
2678 | 4KB. | |
2679 | .TP | |
2680 | .I /proc/kmsg | |
2681 | This file can be used instead of the | |
2682 | .BR syslog (2) | |
c13182ef MK |
2683 | system call to read kernel messages. |
2684 | A process must have superuser | |
fea681da | 2685 | privileges to read this file, and only one process should read this |
c13182ef MK |
2686 | file. |
2687 | This file should not be read if a syslog process is running | |
fea681da MK |
2688 | which uses the |
2689 | .BR syslog (2) | |
2690 | system call facility to log kernel messages. | |
2691 | ||
2692 | Information in this file is retrieved with the | |
c4517613 | 2693 | .BR dmesg (1) |
fea681da MK |
2694 | program. |
2695 | .TP | |
ff56ac8b MK |
2696 | .IR /proc/kpagecount " (since Linux 2.6.25)" |
2697 | This file contains a 64-bit count of the number of | |
2698 | times each physical page frame is mapped, | |
2699 | indexed by page frame number (see the discussion of | |
2700 | .IR /proc/[pid]/pagemap ). | |
2701 | .IP | |
2702 | The | |
2703 | .IR /proc/kpagecount | |
2704 | file is present only if the | |
2705 | .B CONFIG_PROC_PAGE_MONITOR | |
59d566a9 MK |
2706 | kernel configuration option is enabled. |
2707 | .TP | |
2708 | .IR /proc/kpageflags " (since Linux 2.6.25)" | |
ef4f4031 | 2709 | This file contains 64-bit masks corresponding to each physical page frame; |
59d566a9 MK |
2710 | it is indexed by page frame number (see the discussion of |
2711 | .IR /proc/[pid]/pagemap ). | |
2712 | The bits are as follows: | |
2713 | ||
2714 | 0 - KPF_LOCKED | |
2715 | 1 - KPF_ERROR | |
2716 | 2 - KPF_REFERENCED | |
2717 | 3 - KPF_UPTODATE | |
2718 | 4 - KPF_DIRTY | |
2719 | 5 - KPF_LRU | |
2720 | 6 - KPF_ACTIVE | |
2721 | 7 - KPF_SLAB | |
2722 | 8 - KPF_WRITEBACK | |
2723 | 9 - KPF_RECLAIM | |
2724 | 10 - KPF_BUDDY | |
2725 | 11 - KPF_MMAP (since Linux 2.6.31) | |
2726 | 12 - KPF_ANON (since Linux 2.6.31) | |
2727 | 13 - KPF_SWAPCACHE (since Linux 2.6.31) | |
2728 | 14 - KPF_SWAPBACKED (since Linux 2.6.31) | |
2729 | 15 - KPF_COMPOUND_HEAD (since Linux 2.6.31) | |
2730 | 16 - KPF_COMPOUND_TAIL (since Linux 2.6.31) | |
2731 | 16 - KPF_HUGE (since Linux 2.6.31) | |
2732 | 18 - KPF_UNEVICTABLE (since Linux 2.6.31) | |
2733 | 19 - KPF_HWPOISON (since Linux 2.6.31) | |
2734 | 20 - KPF_NOPAGE (since Linux 2.6.31) | |
2735 | 21 - KPF_KSM (since Linux 2.6.32) | |
2736 | 22 - KPF_THP (since Linux 3.4) | |
2737 | ||
2738 | For further details on the meanings of these bits, | |
2739 | see the kernel source file | |
2740 | .IR Documentation/vm/pagemap.txt . | |
2741 | Before kernel 2.6.29, | |
2742 | .\" commit ad3bdefe877afb47480418fdb05ecd42842de65e | |
2743 | .\" commit e07a4b9217d1e97d2f3a62b6b070efdc61212110 | |
2744 | .BR KPF_WRITEBACK , | |
2745 | .BR KPF_RECLAIM , | |
2746 | .BR KPF_BUDDY , | |
2747 | and | |
2748 | .BR KPF_LOCKED | |
2749 | did not report correctly. | |
2750 | .IP | |
2751 | The | |
2752 | .IR /proc/kpageflags | |
2753 | file is present only if the | |
2754 | .B CONFIG_PROC_PAGE_MONITOR | |
ff56ac8b MK |
2755 | kernel configuration option is enabled. |
2756 | .TP | |
fea681da MK |
2757 | .IR /proc/ksyms " (Linux 1.1.23-2.5.47)" |
2758 | See | |
2759 | .IR /proc/kallsyms . | |
2760 | .TP | |
2761 | .I /proc/loadavg | |
6b05dc38 MK |
2762 | The first three fields in this file are load average figures |
2763 | giving the number of jobs in the run queue (state R) | |
fea681da MK |
2764 | or waiting for disk I/O (state D) averaged over 1, 5, and 15 minutes. |
2765 | They are the same as the load average numbers given by | |
2766 | .BR uptime (1) | |
2767 | and other programs. | |
6b05dc38 | 2768 | The fourth field consists of two numbers separated by a slash (/). |
78fc91ec EDB |
2769 | The first of these is the number of currently runnable kernel |
2770 | scheduling entities (processes, threads). | |
6b05dc38 MK |
2771 | The value after the slash is the number of kernel scheduling entities |
2772 | that currently exist on the system. | |
2773 | The fifth field is the PID of the process that was most | |
2774 | recently created on the system. | |
fea681da MK |
2775 | .TP |
2776 | .I /proc/locks | |
2777 | This file shows current file locks | |
2778 | .RB ( flock "(2) and " fcntl (2)) | |
2779 | and leases | |
2780 | .RB ( fcntl (2)). | |
2781 | .TP | |
89dd5f8a | 2782 | .IR /proc/malloc " (only up to and including Linux 2.2)" |
59a40ed7 | 2783 | .\" It looks like this only ever did something back in 1.0 days |
90878f7c | 2784 | This file is present only if |
89dd5f8a | 2785 | .B CONFIG_DEBUG_MALLOC |
097585ed | 2786 | was defined during compilation. |
fea681da MK |
2787 | .TP |
2788 | .I /proc/meminfo | |
77b802ec MK |
2789 | This file reports statistics about memory usage on the system. |
2790 | It is used by | |
fea681da MK |
2791 | .BR free (1) |
2792 | to report the amount of free and used memory (both physical and swap) | |
2793 | on the system as well as the shared memory and buffers used by the | |
2794 | kernel. | |
3ba3d5b1 MK |
2795 | Each line of the file consists of a parameter name, followed by a colon, |
2796 | the value of the parameter, and an option unit of measurement (e.g., "kB"). | |
2797 | The list below describes the parameter names and | |
2798 | the format specifier required to read the field value. | |
2799 | Except as noted below, | |
2800 | all of the fields have been present since at least Linux 2.6.0. | |
86cf87d7 | 2801 | Some fields are displayed only if the kernel was configured |
3ba3d5b1 MK |
2802 | with various options; those dependencies are noted in the list. |
2803 | .RS | |
2804 | .TP | |
2805 | .IR MemTotal " %lu" | |
449dd4e2 | 2806 | Total usable RAM (i.e., physical RAM minus a few reserved |
99e91586 | 2807 | bits and the kernel binary code). |
3ba3d5b1 MK |
2808 | .TP |
2809 | .IR MemFree " %lu" | |
7bccb7d4 DP |
2810 | The sum of |
2811 | .IR LowFree + HighFree . | |
3ba3d5b1 | 2812 | .TP |
8b4b1f68 MK |
2813 | .IR MemAvailable " %lu (since Linux 3.14)" |
2814 | An estimate of how much memory is available for starting new | |
2815 | applications, without swapping. | |
2816 | .TP | |
3ba3d5b1 | 2817 | .IR Buffers " %lu" |
99e91586 | 2818 | Relatively temporary storage for raw disk blocks that |
3ba3d5b1 MK |
2819 | shouldn't get tremendously large (20MB or so). |
2820 | .TP | |
2821 | .IR Cached " %lu" | |
2822 | In-memory cache for files read from the disk (the page cache). | |
2823 | Doesn't include | |
2824 | .IR SwapCached . | |
2825 | .TP | |
2826 | .IR SwapCached " %lu" | |
2827 | Memory that once was swapped out, is swapped back in but | |
2828 | still also is in the swap file. | |
fa1d2749 | 2829 | (If memory pressure is high, these pages |
3ba3d5b1 | 2830 | don't need to be swapped out again because they are already |
99e91586 | 2831 | in the swap file. |
3ba3d5b1 MK |
2832 | This saves I/O.) |
2833 | .TP | |
2834 | .IR Active " %lu" | |
2835 | Memory that has been used more recently and usually not | |
2836 | reclaimed unless absolutely necessary. | |
2837 | .TP | |
2838 | .IR Inactive " %lu" | |
2839 | Memory which has been less recently used. | |
2840 | It is more eligible to be reclaimed for other purposes. | |
2841 | .TP | |
2842 | .IR Active(anon) " %lu (since Linux 2.6.28)" | |
2843 | [To be documented.] | |
2844 | .TP | |
2845 | .IR Inactive(anon) " %lu (since Linux 2.6.28)" | |
2846 | [To be documented.] | |
2847 | .TP | |
2848 | .IR Active(file) " %lu (since Linux 2.6.28)" | |
2849 | [To be documented.] | |
2850 | .TP | |
2851 | .IR Inactive(file) " %lu (since Linux 2.6.28)" | |
2852 | [To be documented.] | |
2853 | .TP | |
2854 | .IR Unevictable " %lu (since Linux 2.6.28)" | |
2855 | (From Linux 2.6.28 to 2.6.30, | |
2856 | \fBCONFIG_UNEVICTABLE_LRU\fP was required.) | |
2857 | [To be documented.] | |
2858 | .TP | |
46fbfc07 | 2859 | .IR Mlocked " %lu (since Linux 2.6.28)" |
3ba3d5b1 MK |
2860 | (From Linux 2.6.28 to 2.6.30, |
2861 | \fBCONFIG_UNEVICTABLE_LRU\fP was required.) | |
2862 | [To be documented.] | |
2863 | .TP | |
2864 | .IR HighTotal " %lu" | |
2865 | (Starting with Linux 2.6.19, \fBCONFIG_HIGHMEM\fP is required.) | |
2866 | Total amount of highmem. | |
99e91586 | 2867 | Highmem is all memory above ~860MB of physical memory. |
3ba3d5b1 MK |
2868 | Highmem areas are for use by user-space programs, |
2869 | or for the page cache. | |
2870 | The kernel must use tricks to access | |
2871 | this memory, making it slower to access than lowmem. | |
2872 | .TP | |
2873 | .IR HighFree " %lu | |
2874 | (Starting with Linux 2.6.19, \fBCONFIG_HIGHMEM\fP is required.) | |
2875 | Amount of free highmem. | |
2876 | .TP | |
2877 | .IR LowTotal " %lu | |
2878 | (Starting with Linux 2.6.19, \fBCONFIG_HIGHMEM\fP is required.) | |
2879 | Total amount of lowmem. | |
2880 | Lowmem is memory which can be used for everything that | |
2881 | highmem can be used for, but it is also available for the | |
2882 | kernel's use for its own data structures. | |
2883 | Among many other things, | |
99e91586 | 2884 | it is where everything from |
7bccb7d4 DP |
2885 | .I Slab |
2886 | is allocated. | |
3ba3d5b1 MK |
2887 | Bad things happen when you're out of lowmem. |
2888 | .TP | |
2889 | .IR LowFree " %lu | |
2890 | (Starting with Linux 2.6.19, \fBCONFIG_HIGHMEM\fP is required.) | |
2891 | Amount of free lowmem. | |
2892 | .TP | |
2893 | .IR MmapCopy " %lu (since Linux 2.6.29)" | |
99e91586 DP |
2894 | .RB ( CONFIG_MMU |
2895 | is required.) | |
3ba3d5b1 MK |
2896 | [To be documented.] |
2897 | .TP | |
2898 | .IR SwapTotal " %lu" | |
2899 | Total amount of swap space available. | |
2900 | .TP | |
2901 | .IR SwapFree " %lu" | |
c16d4f25 | 2902 | Amount of swap space that is currently unused. |
3ba3d5b1 MK |
2903 | .TP |
2904 | .IR Dirty " %lu" | |
2905 | Memory which is waiting to get written back to the disk. | |
2906 | .TP | |
2907 | .IR Writeback " %lu" | |
2908 | Memory which is actively being written back to the disk. | |
2909 | .TP | |
2910 | .IR AnonPages " %lu (since Linux 2.6.18)" | |
2911 | Non-file backed pages mapped into user-space page tables. | |
2912 | .TP | |
2913 | .IR Mapped " %lu" | |
fda70f5b MK |
2914 | Files which have been mapped into memory (with |
2915 | .BR mmap (2)), | |
2916 | such as libraries. | |
3ba3d5b1 MK |
2917 | .TP |
2918 | .IR Shmem " %lu (since Linux 2.6.32)" | |
2919 | [To be documented.] | |
2920 | .TP | |
2921 | .IR Slab " %lu" | |
2922 | In-kernel data structures cache. | |
2923 | .TP | |
2924 | .IR SReclaimable " %lu (since Linux 2.6.19)" | |
7bccb7d4 DP |
2925 | Part of |
2926 | .IR Slab , | |
2927 | that might be reclaimed, such as caches. | |
3ba3d5b1 MK |
2928 | .TP |
2929 | .IR SUnreclaim " %lu (since Linux 2.6.19)" | |
7bccb7d4 DP |
2930 | Part of |
2931 | .IR Slab , | |
2932 | that cannot be reclaimed on memory pressure. | |
3ba3d5b1 MK |
2933 | .TP |
2934 | .IR KernelStack " %lu (since Linux 2.6.32)" | |
2935 | Amount of memory allocated to kernel stacks. | |
2936 | .TP | |
2937 | .IR PageTables " %lu (since Linux 2.6.18)" | |
2938 | Amount of memory dedicated to the lowest level of page tables. | |
2939 | .TP | |
2940 | .IR Quicklists " %lu (since Linux 2.6.27)" | |
2941 | (\fBCONFIG_QUICKLIST\fP is required.) | |
2942 | [To be documented.] | |
2943 | .TP | |
2944 | .IR NFS_Unstable " %lu (since Linux 2.6.18)" | |
2945 | NFS pages sent to the server, but not yet committed to stable storage. | |
2946 | .TP | |
2947 | .IR Bounce " %lu (since Linux 2.6.18)" | |
2948 | Memory used for block device "bounce buffers". | |
2949 | .TP | |
2950 | .IR WritebackTmp " %lu (since Linux 2.6.26)" | |
2951 | Memory used by FUSE for temporary writeback buffers. | |
2952 | .TP | |
2953 | .IR CommitLimit " %lu (since Linux 2.6.10)" | |
cd7b6c40 MK |
2954 | This is the total amount of memory currently available to |
2955 | be allocated on the system, expressed in kilobytes. | |
90878f7c MK |
2956 | This limit is adhered to |
2957 | only if strict overcommit accounting is enabled (mode 2 in | |
cd7b6c40 MK |
2958 | .IR /proc/sys/vm/overcommit_memory ). |
2959 | The limit is calculated according to the formula described under | |
2960 | .IR /proc/sys/vm/overcommit_memory . | |
2961 | For further details, see the kernel source file | |
3ba3d5b1 MK |
2962 | .IR Documentation/vm/overcommit-accounting . |
2963 | .TP | |
2964 | .IR Committed_AS " %lu" | |
2965 | The amount of memory presently allocated on the system. | |
2966 | The committed memory is a sum of all of the memory which | |
2967 | has been allocated by processes, even if it has not been | |
2968 | "used" by them as of yet. | |
2969 | A process which allocates 1GB of memory (using | |
2970 | .BR malloc (3) | |
33a0ccb2 | 2971 | or similar), but touches only 300MB of that memory will show up |
90878f7c | 2972 | as using only 300MB of memory even if it has the address space |
3ba3d5b1 | 2973 | allocated for the entire 1GB. |
cd7b6c40 | 2974 | |
3ba3d5b1 MK |
2975 | This 1GB is memory which has been "committed" to by the VM |
2976 | and can be used at any time by the allocating application. | |
cd7b6c40 | 2977 | With strict overcommit enabled on the system (mode 2 in |
d9e0f03d | 2978 | .IR /proc/sys/vm/overcommit_memory ), |
3ba3d5b1 MK |
2979 | allocations which would exceed the |
2980 | .I CommitLimit | |
cd7b6c40 | 2981 | will not be permitted. |
3ba3d5b1 MK |
2982 | This is useful if one needs to guarantee that processes will not |
2983 | fail due to lack of memory once that memory has been successfully allocated. | |
2984 | .TP | |
2985 | .IR VmallocTotal " %lu" | |
2986 | Total size of vmalloc memory area. | |
2987 | .TP | |
2988 | .IR VmallocUsed " %lu" | |
2989 | Amount of vmalloc area which is used. | |
2990 | .TP | |
2991 | .IR VmallocChunk " %lu" | |
2992 | Largest contiguous block of vmalloc area which is free. | |
2993 | .TP | |
2994 | .IR HardwareCorrupted " %lu (since Linux 2.6.32)" | |
2995 | (\fBCONFIG_MEMORY_FAILURE\fP is required.) | |
2996 | [To be documented.] | |
2997 | .TP | |
2998 | .IR AnonHugePages " %lu (since Linux 2.6.38)" | |
2999 | (\fBCONFIG_TRANSPARENT_HUGEPAGE\fP is required.) | |
7fac88a9 | 3000 | Non-file backed huge pages mapped into user-space page tables. |
3ba3d5b1 | 3001 | .TP |
43179f55 MK |
3002 | .IR CmaTotal " %lu (since Linux 3.1)" |
3003 | Total CMA (Contiguous Memory Allocator) pages. | |
3004 | (\fBCONFIG_CMA\fP is required.) | |
3005 | .TP | |
3006 | .IR CmaFree " %lu (since Linux 3.1)" | |
3007 | Free CMA (Contiguous Memory Allocator) pages. | |
3008 | (\fBCONFIG_CMA\fP is required.) | |
3009 | .TP | |
3ba3d5b1 MK |
3010 | .IR HugePages_Total " %lu" |
3011 | (\fBCONFIG_HUGETLB_PAGE\fP is required.) | |
3012 | The size of the pool of huge pages. | |
3013 | .TP | |
3014 | .IR HugePages_Free " %lu" | |
3015 | (\fBCONFIG_HUGETLB_PAGE\fP is required.) | |
3016 | The number of huge pages in the pool that are not yet allocated. | |
3017 | .TP | |
3018 | .IR HugePages_Rsvd " %lu (since Linux 2.6.17)" | |
3019 | (\fBCONFIG_HUGETLB_PAGE\fP is required.) | |
3020 | This is the number of huge pages for | |
3021 | which a commitment to allocate from the pool has been made, | |
3022 | but no allocation has yet been made. | |
3023 | These reserved huge pages | |
3024 | guarantee that an application will be able to allocate a | |
3025 | huge page from the pool of huge pages at fault time. | |
3026 | .TP | |
aa8a6b4f | 3027 | .IR HugePages_Surp " %lu (since Linux 2.6.24)" |
3ba3d5b1 MK |
3028 | (\fBCONFIG_HUGETLB_PAGE\fP is required.) |
3029 | This is the number of huge pages in | |
3030 | the pool above the value in | |
3031 | .IR /proc/sys/vm/nr_hugepages . | |
3032 | The maximum number of surplus huge pages is controlled by | |
3033 | .IR /proc/sys/vm/nr_overcommit_hugepages . | |
3034 | .TP | |
3035 | .IR Hugepagesize " %lu" | |
3036 | (\fBCONFIG_HUGETLB_PAGE\fP is required.) | |
3037 | The size of huge pages. | |
d5268de1 MK |
3038 | .TP |
3039 | .IR DirectMap4k " %lu (since Linux 2.6.27)" | |
3040 | Number of bytes of RAM linearly mapped by kernel in 4kB pages. | |
3041 | (x86.) | |
3042 | .TP | |
3043 | .IR DirectMap4M " %lu (since Linux 2.6.27)" | |
3044 | Number of bytes of RAM linearly mapped by kernel in 4MB pages. | |
3045 | (x86 with | |
3046 | .BR CONFIG_X86_64 | |
3047 | or | |
3048 | .BR CONFIG_X86_PAE | |
3049 | enabled.) | |
3050 | .TP | |
3051 | .IR DirectMap2M " %lu (since Linux 2.6.27)" | |
3052 | Number of bytes of RAM linearly mapped by kernel in 2MB pages. | |
3053 | (x86 with neither | |
3054 | .BR CONFIG_X86_64 | |
3055 | nor | |
3056 | .BR CONFIG_X86_PAE | |
3057 | enabled.) | |
3058 | .TP | |
3059 | .IR DirectMap1G " %lu (since Linux 2.6.27)" | |
3060 | (x86 with | |
3061 | .BR CONFIG_X86_64 | |
3062 | and | |
3063 | .B CONFIG_X86_DIRECT_GBPAGES | |
3064 | enabled.) | |
3ba3d5b1 | 3065 | .RE |
fea681da | 3066 | .TP |
aa341984 MK |
3067 | .I /proc/modules |
3068 | A text list of the modules that have been loaded by the system. | |
3069 | See also | |
3070 | .BR lsmod (8). | |
3071 | .TP | |
fea681da | 3072 | .I /proc/mounts |
c1eea65a | 3073 | Before kernel 2.4.19, this file was a list |
9ee4a2b6 | 3074 | of all the filesystems currently mounted on the system. |
ef5b47f6 MK |
3075 | With the introduction of per-process mount namespaces in Linux 2.4.19 (see |
3076 | .BR mount_namespaces (7)), | |
3077 | this file became a link to | |
c1eea65a | 3078 | .IR /proc/self/mounts , |
732e54dd | 3079 | which lists the mount points of the process's own mount namespace. |
fea681da | 3080 | The format of this file is documented in |
31e9a9ec | 3081 | .BR fstab (5). |
fea681da | 3082 | .TP |
fea681da | 3083 | .I /proc/mtrr |
c13182ef | 3084 | Memory Type Range Registers. |
66a9882e | 3085 | See the Linux kernel source file |
cfe70b66 | 3086 | .I Documentation/mtrr.txt |
fea681da MK |
3087 | for details. |
3088 | .TP | |
3089 | .I /proc/net | |
ccb4bcdc MK |
3090 | This directory contains various files and subdirectories containing |
3091 | information about the networking layer. | |
3092 | The files contain ASCII structures and are, | |
59a40ed7 MK |
3093 | therefore, readable with |
3094 | .BR cat (1). | |
c13182ef | 3095 | However, the standard |
fea681da MK |
3096 | .BR netstat (8) |
3097 | suite provides much cleaner access to these files. | |
9fb88bc8 MK |
3098 | |
3099 | With the advent of network namespaces, | |
3100 | various information relating to the network stack is virtualized (see | |
3101 | .BR namespaces (7)). | |
3102 | Thus, since Linux 2.6.25, | |
3103 | .\" commit e9720acd728a46cb40daa52c99a979f7c4ff195c | |
3104 | .IR /proc/net | |
3105 | is a symbolic link to the directory | |
3106 | .IR /proc/self/net , | |
3107 | which contains the same files and directories as listed below. | |
3108 | However, these files and directories now expose information | |
3109 | for the network namespace of which the process is a member. | |
fea681da MK |
3110 | .TP |
3111 | .I /proc/net/arp | |
3112 | This holds an ASCII readable dump of the kernel ARP table used for | |
c13182ef | 3113 | address resolutions. |
01d0a447 | 3114 | It will show both dynamically learned and preprogrammed ARP entries. |
c13182ef | 3115 | The format is: |
fea681da MK |
3116 | |
3117 | .nf | |
3118 | .ft CW | |
3119 | .in 8n | |
3120 | IP address HW type Flags HW address Mask Device | |
3121 | 192.168.0.50 0x1 0x2 00:50:BF:25:68:F3 * eth0 | |
3122 | 192.168.0.250 0x1 0xc 00:00:00:00:00:00 * eth0 | |
3123 | .ft | |
3124 | .fi | |
3125 | .in | |
3126 | ||
6c04f928 | 3127 | Here "IP address" is the IPv4 address of the machine and the "HW type" |
c13182ef MK |
3128 | is the hardware type of the address from RFC\ 826. |
3129 | The flags are the internal | |
9a67332e MK |
3130 | flags of the ARP structure (as defined in |
3131 | .IR /usr/include/linux/if_arp.h ) | |
3132 | and | |
6c04f928 | 3133 | the "HW address" is the data link layer mapping for that IP address if |
fea681da MK |
3134 | it is known. |
3135 | .TP | |
3136 | .I /proc/net/dev | |
c13182ef MK |
3137 | The dev pseudo-file contains network device status information. |
3138 | This gives | |
3139 | the number of received and sent packets, the number of errors and | |
fea681da | 3140 | collisions |
c13182ef MK |
3141 | and other basic statistics. |
3142 | These are used by the | |
fea681da | 3143 | .BR ifconfig (8) |
c13182ef MK |
3144 | program to report device status. |
3145 | The format is: | |
fea681da MK |
3146 | |
3147 | .nf | |
3148 | .ft CW | |
3149 | .in 1n | |
3150 | Inter-| Receive | Transmit | |
3151 | face |bytes packets errs drop fifo frame compressed multicast|bytes packets errs drop fifo colls carrier compressed | |
3152 | lo: 2776770 11307 0 0 0 0 0 0 2776770 11307 0 0 0 0 0 0 | |
3153 | eth0: 1215645 2751 0 0 0 0 0 0 1782404 4324 0 0 0 427 0 0 | |
3154 | ppp0: 1622270 5552 1 0 0 0 0 0 354130 5669 0 0 0 0 0 0 | |
3155 | tap0: 7714 81 0 0 0 0 0 0 7714 81 0 0 0 0 0 0 | |
3156 | .in | |
3157 | .ft | |
3158 | .fi | |
3159 | .\" .TP | |
3160 | .\" .I /proc/net/ipx | |
3161 | .\" No information. | |
3162 | .\" .TP | |
3163 | .\" .I /proc/net/ipx_route | |
3164 | .\" No information. | |
3165 | .TP | |
3166 | .I /proc/net/dev_mcast | |
3167 | Defined in | |
3168 | .IR /usr/src/linux/net/core/dev_mcast.c : | |
3169 | .nf | |
3170 | .in +5 | |
9fdfa163 | 3171 | indx interface_name dmi_u dmi_g dmi_address |
fea681da MK |
3172 | 2 eth0 1 0 01005e000001 |
3173 | 3 eth1 1 0 01005e000001 | |
3174 | 4 eth2 1 0 01005e000001 | |
3175 | .in | |
3176 | .fi | |
3177 | .TP | |
3178 | .I /proc/net/igmp | |
c13182ef MK |
3179 | Internet Group Management Protocol. |
3180 | Defined in | |
fea681da MK |
3181 | .IR /usr/src/linux/net/core/igmp.c . |
3182 | .TP | |
3183 | .I /proc/net/rarp | |
3184 | This file uses the same format as the | |
3185 | .I arp | |
3186 | file and contains the current reverse mapping database used to provide | |
3187 | .BR rarp (8) | |
c13182ef MK |
3188 | reverse address lookup services. |
3189 | If RARP is not configured into the | |
fea681da MK |
3190 | kernel, |
3191 | this file will not be present. | |
3192 | .TP | |
3193 | .I /proc/net/raw | |
c13182ef MK |
3194 | Holds a dump of the RAW socket table. |
3195 | Much of the information is not of | |
fea681da | 3196 | use |
c13182ef | 3197 | apart from debugging. |
6c04f928 | 3198 | The "sl" value is the kernel hash slot for the |
fea681da | 3199 | socket, |
6c04f928 MK |
3200 | the "local_address" is the local address and protocol number pair. |
3201 | \&"St" is | |
c13182ef MK |
3202 | the internal status of the socket. |
3203 | The "tx_queue" and "rx_queue" are the | |
fea681da | 3204 | outgoing and incoming data queue in terms of kernel memory usage. |
94e9d9fe | 3205 | The "tr", "tm\->when", and "rexmits" fields are not used by RAW. |
fdc196f5 MK |
3206 | The "uid" |
3207 | field holds the effective UID of the creator of the socket. | |
fea681da MK |
3208 | .\" .TP |
3209 | .\" .I /proc/net/route | |
3210 | .\" No information, but looks similar to | |
3211 | .\" .BR route (8). | |
3212 | .TP | |
3213 | .I /proc/net/snmp | |
c13182ef | 3214 | This file holds the ASCII data needed for the IP, ICMP, TCP, and UDP |
fea681da | 3215 | management |
763f0e47 | 3216 | information bases for an SNMP agent. |
fea681da MK |
3217 | .TP |
3218 | .I /proc/net/tcp | |
c13182ef MK |
3219 | Holds a dump of the TCP socket table. |
3220 | Much of the information is not | |
3221 | of use apart from debugging. | |
3222 | The "sl" value is the kernel hash slot | |
6beb1671 MK |
3223 | for the socket, the "local_address" is the local address and port number pair. |
3224 | The "rem_address" is the remote address and port number pair | |
6c04f928 MK |
3225 | (if connected). |
3226 | \&"St" is the internal status of the socket. | |
3227 | The "tx_queue" and "rx_queue" are the | |
fea681da | 3228 | outgoing and incoming data queue in terms of kernel memory usage. |
94e9d9fe | 3229 | The "tr", "tm\->when", and "rexmits" fields hold internal information of |
f33774c4 | 3230 | the kernel socket state and are useful only for debugging. |
fdc196f5 MK |
3231 | The "uid" |
3232 | field holds the effective UID of the creator of the socket. | |
fea681da MK |
3233 | .TP |
3234 | .I /proc/net/udp | |
c13182ef MK |
3235 | Holds a dump of the UDP socket table. |
3236 | Much of the information is not of | |
3237 | use apart from debugging. | |
3238 | The "sl" value is the kernel hash slot for the | |
6beb1671 MK |
3239 | socket, the "local_address" is the local address and port number pair. |
3240 | The "rem_address" is the remote address and port number pair | |
f2d607ee MK |
3241 | (if connected). |
3242 | "St" is the internal status of the socket. | |
fea681da | 3243 | The "tx_queue" and "rx_queue" are the outgoing and incoming data queue |
c13182ef | 3244 | in terms of kernel memory usage. |
94e9d9fe | 3245 | The "tr", "tm\->when", and "rexmits" fields |
c13182ef | 3246 | are not used by UDP. |
fdc196f5 MK |
3247 | The "uid" |
3248 | field holds the effective UID of the creator of the socket. | |
fea681da MK |
3249 | The format is: |
3250 | ||
3251 | .nf | |
3252 | .ft CW | |
3253 | .in 1n | |
94e9d9fe | 3254 | sl local_address rem_address st tx_queue rx_queue tr rexmits tm\->when uid |
fea681da MK |
3255 | 1: 01642C89:0201 0C642C89:03FF 01 00000000:00000001 01:000071BA 00000000 0 |
3256 | 1: 00000000:0801 00000000:0000 0A 00000000:00000000 00:00000000 6F000100 0 | |
3257 | 1: 00000000:0201 00000000:0000 0A 00000000:00000000 00:00000000 00000000 0 | |
3258 | .in | |
3259 | .ft | |
3260 | .fi | |
3261 | .TP | |
3262 | .I /proc/net/unix | |
008f1ecc | 3263 | Lists the UNIX domain sockets present within the system and their |
c13182ef MK |
3264 | status. |
3265 | The format is: | |
fea681da MK |
3266 | .nf |
3267 | .sp .5 | |
3268 | .ft CW | |
3269 | Num RefCount Protocol Flags Type St Path | |
3270 | 0: 00000002 00000000 00000000 0001 03 | |
3271 | 1: 00000001 00000000 00010000 0001 01 /dev/printer | |
3272 | .ft | |
3273 | .sp .5 | |
3274 | .fi | |
3275 | ||
756f55f6 MK |
3276 | The fields are as follows: |
3277 | .RS | |
3278 | .TP 10 | |
3279 | .IR Num : | |
3280 | the kernel table slot number. | |
3281 | .TP | |
3282 | .IR RefCount : | |
3283 | the number of users of the socket. | |
3284 | .TP | |
3285 | .IR Protocol : | |
3286 | currently always 0. | |
3287 | .TP | |
3288 | .IR Flags : | |
3289 | the internal kernel flags holding the status of the socket. | |
3290 | .TP | |
3291 | .IR Type : | |
a405066e MK |
3292 | the socket type. |
3293 | For | |
3294 | .BR SOCK_STREAM | |
3295 | sockets, this is 0001; for | |
3296 | .BR SOCK_DGRAM | |
3297 | sockets, it is 0002; and for | |
3298 | .BR SOCK_SEQPACKET | |
3299 | sockets, it is 0005. | |
756f55f6 MK |
3300 | .TP |
3301 | .IR St : | |
3302 | the internal state of the socket. | |
3303 | .TP | |
3304 | .IR Path : | |
3305 | the bound path (if any) of the socket. | |
8f8a46fb MK |
3306 | Sockets in the abstract namespace are included in the list, |
3307 | and are shown with a | |
3308 | .I Path | |
3309 | that commences with the character '@'. | |
756f55f6 | 3310 | .RE |
fea681da | 3311 | .TP |
ed8de0e4 FW |
3312 | .I /proc/net/netfilter/nfnetlink_queue |
3313 | This file contains information about netfilter userspace queueing, if used. | |
f2d607ee MK |
3314 | Each line represents a queue. |
3315 | Queues that have not been subscribed to | |
ed8de0e4 FW |
3316 | by userspace are not shown. |
3317 | .nf | |
3318 | ||
3319 | 1 4207 0 2 65535 0 0 0 1 | |
3320 | (1) (2) (3)(4) (5) (6) (7) (8) | |
3321 | .fi | |
3322 | .IP | |
3323 | The fields in each line are: | |
3324 | .RS 7 | |
3325 | .TP 5 | |
3326 | (1) | |
f2d607ee MK |
3327 | The ID of the queue. |
3328 | This matches what is specified in the | |
ed8de0e4 FW |
3329 | .B \-\-queue\-num |
3330 | or | |
3331 | .B \-\-queue\-balance | |
3332 | options to the | |
3333 | .BR iptables (8) | |
f2d607ee MK |
3334 | NFQUEUE target. |
3335 | See | |
ed8de0e4 FW |
3336 | .BR iptables-extensions (8) |
3337 | for more information. | |
3338 | .TP | |
3339 | (2) | |
7672e08e | 3340 | The netlink port ID subscribed to the queue. |
ed8de0e4 FW |
3341 | .TP |
3342 | (3) | |
3343 | The number of packets currently queued and waiting to be processed by | |
3344 | the application. | |
3345 | .TP | |
3346 | (4) | |
f2d607ee MK |
3347 | The copy mode of the queue. |
3348 | It is either 1 (metadata only) or 2 | |
ed8de0e4 FW |
3349 | (also copy payload data to userspace). |
3350 | .TP | |
3351 | (5) | |
1dea597b | 3352 | Copy range; that is, how many bytes of packet payload should be copied to |
ed8de0e4 FW |
3353 | userspace at most. |
3354 | .TP | |
3355 | (6) | |
f2d607ee MK |
3356 | queue dropped. |
3357 | Number of packets that had to be dropped by the kernel because | |
ed8de0e4 FW |
3358 | too many packets are already waiting for userspace to send back the mandatory |
3359 | accept/drop verdicts. | |
3360 | .TP | |
3361 | (7) | |
f2d607ee MK |
3362 | queue user dropped. |
3363 | Number of packets that were dropped within the netlink | |
3364 | subsystem. | |
3365 | Such drops usually happen when the corresponding socket buffer is | |
1dea597b | 3366 | full; that is, userspace is not able to read messages fast enough. |
ed8de0e4 FW |
3367 | .TP |
3368 | (8) | |
f2d607ee MK |
3369 | sequence number. |
3370 | Every queued packet is associated with a (32-bit) | |
ed8de0e4 FW |
3371 | monotonically-increasing sequence number. |
3372 | This shows the ID of the most recent packet queued. | |
3373 | .RE | |
3374 | .IP | |
f33774c4 | 3375 | The last number exists only for compatibility reasons and is always 1. |
ed8de0e4 | 3376 | .TP |
fea681da | 3377 | .I /proc/partitions |
f042d149 MK |
3378 | Contains the major and minor numbers of each partition as well as the number |
3379 | of 1024-byte blocks and the partition name. | |
fea681da MK |
3380 | .TP |
3381 | .I /proc/pci | |
3382 | This is a listing of all PCI devices found during kernel initialization | |
3383 | and their configuration. | |
2990d781 | 3384 | |
59a40ed7 MK |
3385 | This file has been deprecated in favor of a new |
3386 | .I /proc | |
2990d781 MK |
3387 | interface for PCI |
3388 | .RI ( /proc/bus/pci ). | |
3389 | It became optional in Linux 2.2 (available with | |
3390 | .B CONFIG_PCI_OLD_PROC | |
3391 | set at kernel compilation). | |
24b74457 | 3392 | It became once more nonoptionally enabled in Linux 2.4. |
2990d781 MK |
3393 | Next, it was deprecated in Linux 2.6 (still available with |
3394 | .B CONFIG_PCI_LEGACY_PROC | |
3395 | set), and finally removed altogether since Linux 2.6.17. | |
bea08fec MK |
3396 | .\" FIXME Document /proc/sched_debug |
3397 | .\" | |
b4e9ee8f MK |
3398 | .\" .TP |
3399 | .\" .IR /proc/sched_debug " (since Linux 2.6.23)" | |
69119dc7 | 3400 | .\" See also /proc/[pid]/sched |
caea7868 MK |
3401 | .TP |
3402 | .IR /proc/profile " (since Linux 2.4)" | |
3403 | This file is present only if the kernel was booted with the | |
3404 | .I profile=1 | |
3405 | command-line option. | |
3406 | It exposes kernel profiling information in a binary format for use by | |
3407 | .BR readprofile (1). | |
3408 | Writing (e.g., an empty string) to this file resets the profiling counters; | |
3409 | on some architectures, | |
3410 | writing a binary integer "profiling multiplier" of size | |
3411 | .IR sizeof(int) | |
8a3ac89a | 3412 | sets the profiling interrupt frequency. |
fea681da MK |
3413 | .TP |
3414 | .I /proc/scsi | |
59a40ed7 MK |
3415 | A directory with the |
3416 | .I scsi | |
3417 | mid-level pseudo-file and various SCSI low-level | |
2990d781 MK |
3418 | driver directories, |
3419 | which contain a file for each SCSI host in this system, all of | |
c13182ef MK |
3420 | which give the status of some part of the SCSI IO subsystem. |
3421 | These files contain ASCII structures and are, therefore, readable with | |
2990d781 | 3422 | .BR cat (1). |
fea681da | 3423 | |
c13182ef | 3424 | You can also write to some of the files to reconfigure the subsystem or |
59a40ed7 | 3425 | switch certain features on or off. |
fea681da MK |
3426 | .TP |
3427 | .I /proc/scsi/scsi | |
c13182ef | 3428 | This is a listing of all SCSI devices known to the kernel. |
59a40ed7 | 3429 | The listing is similar to the one seen during bootup. |
c13182ef | 3430 | scsi currently supports only the \fIadd-single-device\fP command which |
59a40ed7 MK |
3431 | allows root to add a hotplugged device to the list of known devices. |
3432 | ||
3433 | The command | |
3434 | .in +4n | |
3435 | .nf | |
3436 | ||
3437 | echo \(aqscsi add-single-device 1 0 5 0\(aq > /proc/scsi/scsi | |
fea681da | 3438 | |
59a40ed7 MK |
3439 | .fi |
3440 | .in | |
c13182ef MK |
3441 | will cause |
3442 | host scsi1 to scan on SCSI channel 0 for a device on ID 5 LUN 0. | |
3443 | If there | |
fea681da MK |
3444 | is already a device known on this address or the address is invalid, an |
3445 | error will be returned. | |
3446 | .TP | |
3447 | .I /proc/scsi/[drivername] | |
c13182ef MK |
3448 | \fI[drivername]\fP can currently be NCR53c7xx, aha152x, aha1542, aha1740, |
3449 | aic7xxx, buslogic, eata_dma, eata_pio, fdomain, in2000, pas16, qlogic, | |
3450 | scsi_debug, seagate, t128, u15-24f, ultrastore, or wd7000. | |
3451 | These directories show up for all drivers that registered at least one | |
59a40ed7 | 3452 | SCSI HBA. |
c13182ef | 3453 | Every directory contains one file per registered host. |
59a40ed7 | 3454 | Every host-file is named after the number the host was assigned during |
c13182ef | 3455 | initialization. |
fea681da | 3456 | |
c13182ef | 3457 | Reading these files will usually show driver and host configuration, |
f78ed33a | 3458 | statistics, and so on. |
fea681da MK |
3459 | |
3460 | Writing to these files allows different things on different hosts. | |
3461 | For example, with the \fIlatency\fP and \fInolatency\fP commands, | |
3462 | root can switch on and off command latency measurement code in the | |
c13182ef MK |
3463 | eata_dma driver. |
3464 | With the \fIlockup\fP and \fIunlock\fP commands, | |
3465 | root can control bus lockups simulated by the scsi_debug driver. | |
fea681da MK |
3466 | .TP |
3467 | .I /proc/self | |
59a40ed7 MK |
3468 | This directory refers to the process accessing the |
3469 | .I /proc | |
9ee4a2b6 | 3470 | filesystem, |
59a40ed7 MK |
3471 | and is identical to the |
3472 | .I /proc | |
3473 | directory named by the process ID of the same process. | |
fea681da MK |
3474 | .TP |
3475 | .I /proc/slabinfo | |
c13182ef | 3476 | Information about kernel caches. |
90878f7c | 3477 | Since Linux 2.6.16 this file is present only if the |
821643a8 MK |
3478 | .B CONFIG_SLAB |
3479 | kernel configuration option is enabled. | |
350038ff | 3480 | The columns in |
38f76cd2 | 3481 | .I /proc/slabinfo |
350038ff | 3482 | are: |
a08ea57c | 3483 | .in +4n |
fea681da | 3484 | .nf |
a08ea57c | 3485 | |
fea681da MK |
3486 | cache-name |
3487 | num-active-objs | |
3488 | total-objs | |
3489 | object-size | |
3490 | num-active-slabs | |
3491 | total-slabs | |
3492 | num-pages-per-slab | |
3493 | .fi | |
a08ea57c MK |
3494 | .in |
3495 | ||
c13182ef | 3496 | See |
fea681da MK |
3497 | .BR slabinfo (5) |
3498 | for details. | |
3499 | .TP | |
3500 | .I /proc/stat | |
c13182ef MK |
3501 | kernel/system statistics. |
3502 | Varies with architecture. | |
3503 | Common | |
fea681da MK |
3504 | entries include: |
3505 | .RS | |
3506 | .TP | |
3507 | \fIcpu 3357 0 4313 1362393\fP | |
bfbfcd18 | 3508 | The amount of time, measured in units of |
268f000b MK |
3509 | USER_HZ (1/100ths of a second on most architectures, use |
3510 | .IR sysconf(_SC_CLK_TCK) | |
3511 | to obtain the right value), | |
b81087ab | 3512 | .\" 1024 on Alpha and ia64 |
ae3b8047 MK |
3513 | that the system spent in various states: |
3514 | .RS | |
3515 | .TP | |
3516 | .I user | |
ea0841f6 | 3517 | (1) Time spent in user mode. |
ae3b8047 MK |
3518 | .TP |
3519 | .I nice | |
0633f951 | 3520 | (2) Time spent in user mode with low priority (nice). |
9f1b9726 | 3521 | .TP |
ae3b8047 | 3522 | .I system |
0633f951 | 3523 | (3) Time spent in system mode. |
ae3b8047 MK |
3524 | .TP |
3525 | .I idle | |
ea0841f6 | 3526 | (4) Time spent in the idle task. |
bea08fec | 3527 | .\" FIXME . Actually, the following info about the /proc/stat 'cpu' field |
e04a1f93 MK |
3528 | .\" does not seem to be quite right (at least in 2.6.12 or 3.6): |
3529 | .\" the idle time in /proc/uptime does not quite match this value | |
3530 | This value should be USER_HZ times the | |
4cb1deb7 MK |
3531 | second entry in the |
3532 | .I /proc/uptime | |
3533 | pseudo-file. | |
ae3b8047 MK |
3534 | .TP |
3535 | .IR iowait " (since Linux 2.5.41)" | |
ea0841f6 | 3536 | (5) Time waiting for I/O to complete. |
ae3b8047 MK |
3537 | .TP |
3538 | .IR irq " (since Linux 2.6.0-test4)" | |
ea0841f6 | 3539 | (6) Time servicing interrupts. |
ae3b8047 | 3540 | .TP |
0633f951 | 3541 | .IR softirq " (since Linux 2.6.0-test4)" |
ea0841f6 | 3542 | (7) Time servicing softirqs. |
ae3b8047 MK |
3543 | .TP |
3544 | .IR steal " (since Linux 2.6.11)" | |
ea0841f6 | 3545 | (8) Stolen time, which is the time spent in other operating systems when |
9de1f6cc | 3546 | running in a virtualized environment |
ae3b8047 MK |
3547 | .TP |
3548 | .IR guest " (since Linux 2.6.24)" | |
0633f951 | 3549 | (9) Time spent running a virtual CPU for guest |
afef1764 | 3550 | operating systems under the control of the Linux kernel. |
14c06953 | 3551 | .\" See Changelog entry for 5e84cfde51cf303d368fcb48f22059f37b3872de |
d4fd4120 MK |
3552 | .TP |
3553 | .IR guest_nice " (since Linux 2.6.33)" | |
3554 | .\" commit ce0e7b28fb75cb003cfc8d0238613aaf1c55e797 | |
3555 | (10) Time spent running a niced guest (virtual CPU for guest | |
3556 | operating systems under the control of the Linux kernel). | |
ae3b8047 | 3557 | .RE |
fea681da MK |
3558 | .TP |
3559 | \fIpage 5741 1808\fP | |
3560 | The number of pages the system paged in and the number that were paged | |
3561 | out (from disk). | |
3562 | .TP | |
3563 | \fIswap 1 0\fP | |
3564 | The number of swap pages that have been brought in and out. | |
3565 | .TP | |
bea08fec | 3566 | .\" FIXME . The following is not the full picture for the 'intr' of |
777f5a9e | 3567 | .\" /proc/stat on 2.6: |
fea681da | 3568 | \fIintr 1462898\fP |
bfbfcd18 MK |
3569 | This line shows counts of interrupts serviced since boot time, |
3570 | for each of the possible system interrupts. | |
d63ff76e | 3571 | The first column is the total of all interrupts serviced |
d6a56978 MK |
3572 | including unnumbered architecture specific interrupts; |
3573 | each subsequent column is the total for that particular numbered interrupt. | |
d63ff76e | 3574 | Unnumbered interrupts are not shown, only summed into the total. |
fea681da MK |
3575 | .TP |
3576 | \fIdisk_io: (2,0):(31,30,5764,1,2) (3,0):\fP... | |
636297e9 | 3577 | (major,disk_idx):(noinfo, read_io_ops, blks_read, write_io_ops, blks_written) |
bfbfcd18 MK |
3578 | .br |
3579 | (Linux 2.4 only) | |
fea681da MK |
3580 | .TP |
3581 | \fIctxt 115315\fP | |
3582 | The number of context switches that the system underwent. | |
3583 | .TP | |
3584 | \fIbtime 769041601\fP | |
f49c451a | 3585 | boot time, in seconds since the Epoch, 1970-01-01 00:00:00 +0000 (UTC). |
fea681da MK |
3586 | .TP |
3587 | \fIprocesses 86031\fP | |
3588 | Number of forks since boot. | |
bfbfcd18 MK |
3589 | .TP |
3590 | \fIprocs_running 6\fP | |
3591 | Number of processes in runnable state. | |
5fab2e7c | 3592 | (Linux 2.5.45 onward.) |
bfbfcd18 MK |
3593 | .TP |
3594 | \fIprocs_blocked 2\fP | |
3595 | Number of processes blocked waiting for I/O to complete. | |
5fab2e7c | 3596 | (Linux 2.5.45 onward.) |
fea681da MK |
3597 | .RE |
3598 | .TP | |
3599 | .I /proc/swaps | |
c13182ef MK |
3600 | Swap areas in use. |
3601 | See also | |
fea681da MK |
3602 | .BR swapon (8). |
3603 | .TP | |
3604 | .I /proc/sys | |
3605 | This directory (present since 1.3.57) contains a number of files | |
3606 | and subdirectories corresponding to kernel variables. | |
3607 | These variables can be read and sometimes modified using | |
9ee4a2b6 | 3608 | the \fI/proc\fP filesystem, and the (deprecated) |
fea681da | 3609 | .BR sysctl (2) |
c13182ef | 3610 | system call. |
84ff8c1e | 3611 | |
e8aa7100 | 3612 | String values may be terminated by either \(aq\\0\(aq or \(aq\\n\(aq. |
84ff8c1e HS |
3613 | |
3614 | Integer and long values may be written either in decimal or in | |
3615 | hexadecimal notation (e.g. 0x3FFF). | |
e8aa7100 MK |
3616 | When writing multiple integer or long values, these may be separated |
3617 | by any of the following whitespace characters: | |
3618 | \(aq\ \(aq, \(aq\\t\(aq, or \(aq\\n\(aq. | |
3619 | Using other separators leads to the error | |
84ff8c1e | 3620 | .BR EINVAL . |
fea681da | 3621 | .TP |
6ab7c0aa | 3622 | .IR /proc/sys/abi " (since Linux 2.4.10)" |
fea681da | 3623 | This directory may contain files with application binary information. |
6ab7c0aa | 3624 | .\" On some systems, it is not present. |
66a9882e | 3625 | See the Linux kernel source file |
6ab7c0aa MK |
3626 | .I Documentation/sysctl/abi.txt |
3627 | for more information. | |
fea681da MK |
3628 | .TP |
3629 | .I /proc/sys/debug | |
3630 | This directory may be empty. | |
3631 | .TP | |
3632 | .I /proc/sys/dev | |
e2badfdf | 3633 | This directory contains device-specific information (e.g., |
9a67332e | 3634 | .IR dev/cdrom/info ). |
fea681da MK |
3635 | On |
3636 | some systems, it may be empty. | |
3637 | .TP | |
3638 | .I /proc/sys/fs | |
49236d3c | 3639 | This directory contains the files and subdirectories for kernel variables |
9ee4a2b6 | 3640 | related to filesystems. |
fea681da MK |
3641 | .TP |
3642 | .I /proc/sys/fs/binfmt_misc | |
c13182ef | 3643 | Documentation for files in this directory can be found |
66a9882e | 3644 | in the Linux kernel sources in |
fea681da MK |
3645 | .IR Documentation/binfmt_misc.txt . |
3646 | .TP | |
59a40ed7 MK |
3647 | .IR /proc/sys/fs/dentry-state " (since Linux 2.2)" |
3648 | This file contains information about the status of the | |
3649 | directory cache (dcache). | |
3650 | The file contains six numbers, | |
c13182ef | 3651 | .IR nr_dentry ", " nr_unused ", " age_limit " (age in seconds), " |
59a40ed7 | 3652 | .I want_pages |
fea681da | 3653 | (pages requested by system) and two dummy values. |
59a40ed7 MK |
3654 | .RS |
3655 | .IP * 2 | |
3656 | .I nr_dentry | |
3657 | is the number of allocated dentries (dcache entries). | |
3658 | This field is unused in Linux 2.2. | |
3659 | .IP * | |
3660 | .I nr_unused | |
3661 | is the number of unused dentries. | |
3662 | .IP * | |
3663 | .I age_limit | |
3664 | .\" looks like this is unused in kernels 2.2 to 2.6 | |
3665 | is the age in seconds after which dcache entries | |
3666 | can be reclaimed when memory is short. | |
3667 | .IP * | |
3668 | .I want_pages | |
3669 | .\" looks like this is unused in kernels 2.2 to 2.6 | |
c7094399 | 3670 | is nonzero when the kernel has called shrink_dcache_pages() and the |
fea681da | 3671 | dcache isn't pruned yet. |
59a40ed7 | 3672 | .RE |
fea681da MK |
3673 | .TP |
3674 | .I /proc/sys/fs/dir-notify-enable | |
3675 | This file can be used to disable or enable the | |
3676 | .I dnotify | |
3677 | interface described in | |
3678 | .BR fcntl (2) | |
3679 | on a system-wide basis. | |
3680 | A value of 0 in this file disables the interface, | |
3681 | and a value of 1 enables it. | |
3682 | .TP | |
3683 | .I /proc/sys/fs/dquot-max | |
3684 | This file shows the maximum number of cached disk quota entries. | |
3685 | On some (2.4) systems, it is not present. | |
3686 | If the number of free cached disk quota entries is very low and | |
3687 | you have some awesome number of simultaneous system users, | |
3688 | you might want to raise the limit. | |
3689 | .TP | |
3690 | .I /proc/sys/fs/dquot-nr | |
3691 | This file shows the number of allocated disk quota | |
3692 | entries and the number of free disk quota entries. | |
3693 | .TP | |
24cb4a4b | 3694 | .IR /proc/sys/fs/epoll " (since Linux 2.6.28)" |
242b46af MK |
3695 | This directory contains the file |
3696 | .IR max_user_watches , | |
24cb4a4b MK |
3697 | which can be used to limit the amount of kernel memory consumed by the |
3698 | .I epoll | |
3699 | interface. | |
3700 | For further details, see | |