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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 | .\" |
c533af9d | 51 | .\" FIXME 2.6.13 seems to have /proc/vmcore implemented |
c13182ef MK |
52 | .\" in the source code, but there is no option available under |
53 | .\" 'make xconfig'; eventually this should be fixed, and then info | |
54 | .\" from the patch-2.6.13 and change log could be used to write an | |
c533af9d | 55 | .\" entry in this man page. |
cc2d5c36 | 56 | .\" Needs CONFIG_VMCORE |
8cf9de1b | 57 | .\" |
c13182ef MK |
58 | .\" FIXME cross check against Documentation/filesystems/proc.txt |
59 | .\" to see what information could be imported from that file | |
c533af9d | 60 | .\" into this file. |
fea681da | 61 | .\" |
8660ef9f | 62 | .TH PROC 5 2014-05-28 "Linux" "Linux Programmer's Manual" |
fea681da | 63 | .SH NAME |
9ee4a2b6 | 64 | proc \- process information pseudo-filesystem |
fea681da MK |
65 | .SH DESCRIPTION |
66 | The | |
67 | .I proc | |
ac8727b6 | 68 | filesystem is a pseudo-filesystem which provides an interface to |
c13182ef MK |
69 | kernel data structures. |
70 | It is commonly mounted at | |
fea681da | 71 | .IR /proc . |
c13182ef | 72 | Most of it is read-only, but some files allow kernel variables to be |
fea681da MK |
73 | changed. |
74 | .LP | |
ac8727b6 | 75 | The following list describes many of the files and directories under the |
743638fd MK |
76 | .I /proc |
77 | hierarchy. | |
fea681da MK |
78 | .PD 1 |
79 | .TP | |
69119dc7 | 80 | .I /proc/[pid] |
fea681da MK |
81 | There is a numerical subdirectory for each running process; the |
82 | subdirectory is named by the process ID. | |
83 | Each such subdirectory contains the following | |
84 | pseudo-files and directories. | |
69119dc7 MK |
85 | .\" FIXME Describe /proc/[pid]/attr and |
86 | .\" /proc/[pid]/task/[tid]/attr | |
b4e9ee8f MK |
87 | .\" This is a directory |
88 | .\" Added in ??? | |
89 | .\" CONFIG_SECURITY | |
90 | .\" | |
fea681da | 91 | .TP |
69119dc7 | 92 | .IR /proc/[pid]/auxv " (since 2.6.0-test7)" |
857f1942 | 93 | This contains the contents of the ELF interpreter information passed |
c13182ef | 94 | to the process at exec time. |
857f1942 | 95 | The format is one \fIunsigned long\fP ID |
c13182ef | 96 | plus one \fIunsigned long\fP value for each entry. |
857f1942 | 97 | The last entry contains two zeros. |
b5d204d0 | 98 | .TP |
8d708d6b | 99 | .IR /proc/[pid]/cgroup " (since Linux 2.6.24)" |
b5d204d0 MK |
100 | .\" Info in Documentation/cgroups/cgroups.txt |
101 | This file describes control groups to which the process/task belongs. | |
102 | For each cgroup hierarchy there is one entry containing | |
103 | colon-separated fields of the form: | |
104 | .nf | |
105 | .ft CW | |
106 | ||
107 | 5:cpuacct,cpu,cpuset:/daemons | |
108 | .ft | |
109 | .fi | |
110 | .IP | |
111 | The colon-separated fields are, from left to right: | |
112 | .RS 11 | |
113 | .IP 1. 3 | |
114 | hierarchy ID number | |
115 | .IP 2. | |
116 | set of subsystems bound to the hierarchy | |
117 | .IP 3. | |
118 | control group in the hierarchy to which the process belongs | |
119 | .RE | |
120 | .IP | |
90878f7c | 121 | This file is present only if the |
b5d204d0 MK |
122 | .B CONFIG_CGROUPS |
123 | kernel configuration option is enabled. | |
76e0451c MK |
124 | .TP |
125 | .IR /proc/[pid]/clear_refs " (since Linux 2.6.22)" | |
126 | .\" commit b813e931b4c8235bb42e301096ea97dbdee3e8fe (2.6.22) | |
127 | .\" commit 398499d5f3613c47f2143b8c54a04efb5d7a6da9 (2.6.32) | |
128 | .\" commit 040fa02077de01c7e08fa75be6125e4ca5636011 (3.11) | |
b4e9ee8f | 129 | .\" |
b4e9ee8f | 130 | .\" "Clears page referenced bits shown in smaps output" |
76e0451c MK |
131 | .\" write-only, writable only by the owner of the process |
132 | ||
133 | This is a write-only file, writable only by owner of the process. | |
134 | ||
135 | The following values may be written to the file: | |
136 | .RS | |
137 | .TP | |
138 | 1 (since Linux 2.6.22) | |
139 | .\" Internally: CLEAR_REFS_ALL | |
140 | Reset the PG_Referenced and ACCESSED/YOUNG | |
141 | bits for all the pages associated with the process. | |
142 | (Before kernel 2.6.32, writing any nonzero value to this file | |
143 | had this effect.) | |
144 | .TP | |
145 | 2 (since Linux 2.6.32) | |
146 | .\" Internally: CLEAR_REFS_ANON | |
147 | Reset the PG_Referenced and ACCESSED/YOUNG | |
148 | bits for all anonymous pages associated with the process. | |
149 | .TP | |
150 | 3 (since Linux 2.6.32) | |
151 | .\" Internally: CLEAR_REFS_MAPPED | |
152 | Reset the PG_Referenced and ACCESSED/YOUNG | |
153 | bits for all file-mapped pages associated with the process. | |
154 | .RE | |
155 | .IP | |
156 | Clearing the PG_Referenced and ACCESSED/YOUNG bits provides a method | |
157 | to measure approximately how much memory a process is using. | |
322d49fb | 158 | One first inspects the values in the "Referenced" fields |
76e0451c MK |
159 | for the VMAs shown in |
160 | .IR /proc/[pid]/smaps | |
161 | to get an idea of the memory footprint of the | |
162 | process. | |
163 | One then clears the PG_Referenced and ACCESSED/YOUNG bits | |
164 | and, after some measured time interval, | |
322d49fb | 165 | once again inspects the values in the "Referenced" fields |
76e0451c MK |
166 | to get an idea of the change in memory footprint of the |
167 | process during the measured interval. | |
168 | If one is interested only in inspecting the selected mapping types, | |
169 | then the value 2 or 3 can be used instead of 1. | |
170 | ||
171 | A further value can be written to affect a different bit: | |
172 | .RS | |
173 | .TP | |
174 | 4 (since Linux 3.11) | |
175 | Clear the soft-dirty bit for all the pages associated with the process. | |
176 | .\" Internally: CLEAR_REFS_SOFT_DIRTY | |
177 | This is used (in conjunction with | |
178 | .IR /proc/[pid]/pagemap ) | |
179 | by the check-point restore system to discover which pages of a process | |
180 | have been dirtied since the file | |
181 | .IR /proc/[pid]/clear_refs | |
182 | was written to. | |
183 | .RE | |
184 | .IP | |
185 | Writing any value to | |
186 | .IR /proc/[pid]/clear_refs | |
187 | other than those listed above has no effect. | |
188 | ||
189 | The | |
190 | .IR /proc/[pid]/clear_refs | |
191 | file is present only if the | |
192 | .B CONFIG_PROC_PAGE_MONITOR | |
193 | kernel configuration option is enabled. | |
857f1942 | 194 | .TP |
69119dc7 | 195 | .I /proc/[pid]/cmdline |
b447cd58 MK |
196 | This holds the complete command line for the process, |
197 | unless the process is a zombie. | |
198 | .\" In 2.3.26, this also used to be true if the process was swapped out. | |
199 | In the latter case, there is nothing in this file: | |
75b94dc3 | 200 | that is, a read on this file will return 0 characters. |
b447cd58 | 201 | The command-line arguments appear in this file as a set of |
6596d270 MK |
202 | strings separated by null bytes (\(aq\\0\(aq), |
203 | with a further null byte after the last string. | |
fea681da | 204 | .TP |
69119dc7 | 205 | .IR /proc/[pid]/coredump_filter " (since kernel 2.6.23)" |
b4e9ee8f MK |
206 | See |
207 | .BR core (5). | |
5c411b17 | 208 | .TP |
69119dc7 MK |
209 | .IR /proc/[pid]/cpuset " (since kernel 2.6.12)" |
210 | .\" and/proc/[pid]/task/[tid]/cpuset | |
5c411b17 MK |
211 | See |
212 | .BR cpuset (7). | |
b4e9ee8f | 213 | .TP |
69119dc7 | 214 | .I /proc/[pid]/cwd |
c13182ef | 215 | This is a symbolic link to the current working directory of the process. |
59a40ed7 MK |
216 | To find out the current working directory of process 20, |
217 | for instance, you can do this: | |
fea681da | 218 | |
59a40ed7 | 219 | .in +4n |
fea681da | 220 | .nf |
b43a3b30 | 221 | .RB "$" " cd /proc/20/cwd; /bin/pwd" |
fea681da | 222 | .fi |
59a40ed7 | 223 | .in |
fea681da | 224 | |
c13182ef MK |
225 | Note that the |
226 | .I pwd | |
e7b489f0 | 227 | command is often a shell built-in, and might |
c13182ef | 228 | not work properly. |
743638fd MK |
229 | In |
230 | .BR bash (1), | |
231 | you may use | |
232 | .IR "pwd\ \-P" . | |
afcaf646 MK |
233 | |
234 | .\" The following was still true as at kernel 2.6.13 | |
c13182ef MK |
235 | In a multithreaded process, the contents of this symbolic link |
236 | are not available if the main thread has already terminated | |
afcaf646 | 237 | (typically by calling |
59a40ed7 | 238 | .BR pthread_exit (3)). |
fea681da | 239 | .TP |
69119dc7 | 240 | .I /proc/[pid]/environ |
fea681da | 241 | This file contains the environment for the process. |
f81fb444 | 242 | The entries are separated by null bytes (\(aq\\0\(aq), |
b4e9ee8f | 243 | and there may be a null byte at the end. |
fea681da | 244 | Thus, to print out the environment of process 1, you would do: |
a08ea57c | 245 | .in +4n |
fea681da | 246 | .nf |
a08ea57c | 247 | |
fea681da | 248 | .ft CW |
13912780 | 249 | .RB "$" " strings /proc/1/environ" |
fea681da MK |
250 | .fi |
251 | .ft P | |
a08ea57c | 252 | .in |
fea681da | 253 | .TP |
69119dc7 | 254 | .I /proc/[pid]/exe |
fea681da | 255 | Under Linux 2.2 and later, this file is a symbolic link |
2d7195b8 | 256 | containing the actual pathname of the executed command. |
c13182ef MK |
257 | This symbolic link can be dereferenced normally; attempting to open |
258 | it will open the executable. | |
259 | You can even type | |
69119dc7 | 260 | .I /proc/[pid]/exe |
c13182ef | 261 | to run another copy of the same executable as is being run by |
69119dc7 | 262 | process [pid]. |
afcaf646 | 263 | .\" The following was still true as at kernel 2.6.13 |
c13182ef MK |
264 | In a multithreaded process, the contents of this symbolic link |
265 | are not available if the main thread has already terminated | |
afcaf646 MK |
266 | (typically by calling |
267 | .BR pthread_exit (3)). | |
fea681da MK |
268 | |
269 | Under Linux 2.0 and earlier | |
69119dc7 | 270 | .I /proc/[pid]/exe |
c13182ef MK |
271 | is a pointer to the binary which was executed, |
272 | and appears as a symbolic link. | |
273 | A | |
fea681da MK |
274 | .BR readlink (2) |
275 | call on this file under Linux 2.0 returns a string in the format: | |
276 | ||
59a40ed7 | 277 | [device]:inode |
fea681da MK |
278 | |
279 | For example, [0301]:1502 would be inode 1502 on device major 03 (IDE, | |
280 | MFM, etc. drives) minor 01 (first partition on the first drive). | |
281 | ||
282 | .BR find (1) | |
59a40ed7 MK |
283 | with the |
284 | .I \-inum | |
285 | option can be used to locate the file. | |
fea681da | 286 | .TP |
d4529654 | 287 | .I /proc/[pid]/fd/ |
fea681da MK |
288 | This is a subdirectory containing one entry for each file which the |
289 | process has open, named by its file descriptor, and which is a | |
c13182ef | 290 | symbolic link to the actual file. |
f78ed33a | 291 | Thus, 0 is standard input, 1 standard output, 2 standard error, and so on. |
fea681da | 292 | |
f75715e0 MK |
293 | For file descriptors for pipes and sockets, |
294 | the entries will be symbolic links whose content is the | |
295 | file type with the inode. | |
d4529654 MF |
296 | A |
297 | .BR readlink (2) | |
298 | call on this file returns a string in the format: | |
f75715e0 | 299 | |
d4529654 | 300 | type:[inode] |
f75715e0 MK |
301 | |
302 | For example, | |
303 | .I socket:[2248868] | |
304 | will be a socket and its inode is 2248868. | |
305 | For sockets, that inode can be used to find more information | |
306 | in one of the files under | |
d4529654 MF |
307 | .IR /proc/net/ . |
308 | ||
2b7a2ac5 MK |
309 | For file descriptors that have no corresponding inode |
310 | (e.g., file descriptors produced by | |
311 | .BR epoll_create (2), | |
312 | .BR eventfd (2), | |
313 | .BR inotify_init (2), | |
314 | .BR signalfd (2), | |
315 | and | |
316 | .BR timerfd (2)), | |
317 | the entry will be a symbolic link with contents of the form | |
318 | ||
319 | anon_inode:<file-type> | |
320 | ||
321 | In some cases, the | |
322 | .I file-type | |
323 | is surrounded by square brackets. | |
324 | ||
325 | For example, an epoll file descriptor will have a symbolic link | |
326 | whose content is the string | |
327 | .IR "anon_inode:[eventpoll]" . | |
328 | ||
d4529654 | 329 | .\"The following was still true as at kernel 2.6.13 |
afcaf646 | 330 | In a multithreaded process, the contents of this directory |
c13182ef | 331 | are not available if the main thread has already terminated |
afcaf646 MK |
332 | (typically by calling |
333 | .BR pthread_exit (3)). | |
334 | ||
59a40ed7 MK |
335 | Programs that will take a filename as a command-line argument, |
336 | but will not take input from standard input if no argument is supplied, | |
337 | or that write to a file named as a command-line argument, | |
338 | but will not send their output to standard output | |
339 | if no argument is supplied, can nevertheless be made to use | |
340 | standard input or standard out using | |
69119dc7 | 341 | .IR /proc/[pid]/fd . |
59a40ed7 MK |
342 | For example, assuming that |
343 | .I \-i | |
344 | is the flag designating an input file and | |
345 | .I \-o | |
346 | is the flag designating an output file: | |
a08ea57c | 347 | .in +4n |
fea681da MK |
348 | .nf |
349 | ||
b43a3b30 | 350 | .RB "$" " foobar \-i /proc/self/fd/0 \-o /proc/self/fd/1 ..." |
fea681da | 351 | .fi |
a08ea57c MK |
352 | .in |
353 | ||
fea681da MK |
354 | and you have a working filter. |
355 | .\" The following is not true in my tests (MTK): | |
356 | .\" Note that this will not work for | |
357 | .\" programs that seek on their files, as the files in the fd directory | |
358 | .\" are not seekable. | |
359 | ||
59a40ed7 MK |
360 | .I /proc/self/fd/N |
361 | is approximately the same as | |
362 | .I /dev/fd/N | |
008f1ecc | 363 | in some UNIX and UNIX-like systems. |
c13182ef | 364 | Most Linux MAKEDEV scripts symbolically link |
59a40ed7 MK |
365 | .I /dev/fd |
366 | to | |
367 | .IR /proc/self/fd , | |
368 | in fact. | |
369 | ||
370 | Most systems provide symbolic links | |
371 | .IR /dev/stdin , | |
372 | .IR /dev/stdout , | |
373 | and | |
374 | .IR /dev/stderr , | |
375 | which respectively link to the files | |
376 | .IR 0 , | |
377 | .IR 1 , | |
378 | and | |
379 | .IR 2 | |
380 | in | |
381 | .IR /proc/self/fd . | |
382 | Thus the example command above could be written as: | |
383 | .in +4n | |
384 | .nf | |
385 | ||
b43a3b30 | 386 | .RB "$" " foobar \-i /dev/stdin \-o /dev/stdout ..." |
59a40ed7 MK |
387 | .fi |
388 | .in | |
69ab425e MK |
389 | .\" FIXME Describe /proc/[pid]/loginuid |
390 | .\" Added in 2.6.11; updating requires CAP_AUDIT_CONTROL | |
391 | .\" CONFIG_AUDITSYSCALL | |
392 | .TP | |
393 | .IR /proc/[pid]/fdinfo/ " (since kernel 2.6.22)" | |
394 | This is a subdirectory containing one entry for each file which the | |
395 | process has open, named by its file descriptor. | |
396 | The contents of each file can be read to obtain information | |
397 | about the corresponding file descriptor, for example: | |
398 | .in +4n | |
399 | .nf | |
400 | ||
401 | .RB "$" " cat /proc/12015/fdinfo/4" | |
402 | pos: 1000 | |
403 | flags: 01002002 | |
404 | .fi | |
405 | .in | |
406 | ||
407 | The | |
408 | .I pos | |
409 | field is a decimal number showing the current file offset. | |
410 | The | |
411 | .I flags | |
412 | field is an octal number that displays the | |
413 | file access mode and file status flags (see | |
414 | .BR open (2)). | |
415 | ||
416 | The files in this directory are readable only by the owner of the process. | |
43a8bfc6 MK |
417 | .\" FIXME |
418 | .\" Certain file types include additional info; see | |
419 | .\" Documentation/filesystems/proc.txt | |
420 | .\" | |
421 | .\" Especially interesting is this: | |
422 | .\" | |
423 | .\" commit ab49bdecc3ebb46ab661f5f05d5c5ea9606406c6 | |
424 | .\" Author: Cyrill Gorcunov <gorcunov@openvz.org> | |
425 | .\" Date: Mon Dec 17 16:05:06 2012 -0800 | |
426 | .\" | |
fa1d49a6 | 427 | .\" Basically, the /proc/PID/fdinfo/ entry for an inotify FD |
43a8bfc6 MK |
428 | .\" includes the file handles for all watched FDs |
429 | .\" | |
0ca2fc4d PS |
430 | .TP |
431 | .IR /proc/[pid]/io " (since kernel 2.6.20)" | |
68f11066 MK |
432 | .\" commit 7c3ab7381e79dfc7db14a67c6f4f3285664e1ec2 |
433 | This file contains I/O statistics for the process, for example: | |
0ca2fc4d PS |
434 | .in +4n |
435 | .nf | |
436 | ||
437 | .RB "#" " cat /proc/3828/io" | |
438 | rchar: 323934931 | |
439 | wchar: 323929600 | |
440 | syscr: 632687 | |
441 | syscw: 632675 | |
442 | read_bytes: 0 | |
443 | write_bytes: 323932160 | |
444 | cancelled_write_bytes: 0 | |
445 | .fi | |
446 | .in | |
447 | ||
448 | The fields are as follows: | |
449 | .RS | |
68f11066 MK |
450 | .TP |
451 | .IR rchar ": characters read" | |
0ca2fc4d PS |
452 | The number of bytes which this task has caused to be read from storage. |
453 | This is simply the sum of bytes which this process passed to | |
454 | .BR read (2) | |
68f11066 | 455 | and similar system calls. |
11256884 | 456 | It includes things such as terminal I/O and |
68f11066 MK |
457 | is unaffected by whether or not actual |
458 | physical disk I/O was required (the read might have been satisfied from | |
0ca2fc4d | 459 | pagecache). |
68f11066 MK |
460 | .TP |
461 | .IR wchar ": characters written" | |
0ca2fc4d PS |
462 | The number of bytes which this task has caused, or shall cause to be written |
463 | to disk. | |
464 | Similar caveats apply here as with | |
465 | .IR rchar . | |
68f11066 MK |
466 | .TP |
467 | .IR syscr ": read syscalls" | |
468 | Attempt to count the number of read I/O operations\(emthat is, | |
469 | system calls such as | |
0ca2fc4d PS |
470 | .BR read (2) |
471 | and | |
472 | .BR pread (2). | |
68f11066 MK |
473 | .TP |
474 | .IR syscw ": write syscalls" | |
475 | Attempt to count the number of write I/O operations\(emthat is, | |
476 | system calls such as | |
0ca2fc4d PS |
477 | .BR write (2) |
478 | and | |
479 | .BR pwrite (2). | |
68f11066 MK |
480 | .TP |
481 | .IR read_bytes ": bytes read" | |
0ca2fc4d PS |
482 | Attempt to count the number of bytes which this process really did cause to |
483 | be fetched from the storage layer. | |
484 | This is accurate for block-backed filesystems. | |
68f11066 MK |
485 | .TP |
486 | .IR write_bytes ": bytes written" | |
0ca2fc4d PS |
487 | Attempt to count the number of bytes which this process caused to be sent to |
488 | the storage layer. | |
68f11066 | 489 | .TP |
0ca2fc4d | 490 | .IR cancelled_write_bytes : |
0ca2fc4d PS |
491 | The big inaccuracy here is truncate. |
492 | If a process writes 1MB to a file and then deletes the file, | |
493 | it will in fact perform no writeout. | |
494 | But it will have been accounted as having caused 1MB of write. | |
68f11066 | 495 | In other words: this field represents the number of bytes which this process |
0ca2fc4d | 496 | caused to not happen, by truncating pagecache. |
68f11066 | 497 | A task can cause "negative" I/O too. |
0ca2fc4d | 498 | If this task truncates some dirty pagecache, |
68f11066 MK |
499 | some I/O which another task has been accounted for |
500 | (in its | |
501 | .IR write_bytes ) | |
502 | will not be happening. | |
503 | .RE | |
0ca2fc4d PS |
504 | .IP |
505 | .IR Note : | |
68f11066 | 506 | In the current implementation, things are a bit racy on 32-bit systems: |
0ca2fc4d PS |
507 | if process A reads process B's |
508 | .I /proc/[pid]/io | |
68f11066 | 509 | while process B is updating one of these 64-bit counters, |
0ca2fc4d | 510 | process A could see an intermediate result. |
69ab425e MK |
511 | .TP |
512 | .IR /proc/[pid]/limits " (since kernel 2.6.24)" | |
513 | This file displays the soft limit, hard limit, and units of measurement | |
514 | for each of the process's resource limits (see | |
515 | .BR getrlimit (2)). | |
516 | Up to and including Linux 2.6.35, | |
517 | this file is protected to allow reading only by the real UID of the process. | |
518 | Since Linux 2.6.36, | |
519 | .\" commit 3036e7b490bf7878c6dae952eec5fb87b1106589 | |
520 | this file is readable by all users on the system. | |
b4f89985 PE |
521 | .TP |
522 | .IR /proc/[pid]/map_files/ " (since kernel 3.3) | |
18cdd0ac MK |
523 | .\" commit 640708a2cff7f81e246243b0073c66e6ece7e53e |
524 | This subdirectory contains entries corresponding to memory-mapped | |
b4f89985 PE |
525 | files (see |
526 | .BR mmap (2)). | |
18cdd0ac MK |
527 | Entries are named by memory region start and end |
528 | address pair (expressed as hexadecimal numbers), | |
529 | and are symbolic links to the mapped files themselves. | |
530 | Here is an example, with the output wrapped and reformatted to fit on an 80-column display: | |
b4f89985 PE |
531 | .in +4n |
532 | .nf | |
533 | ||
7d2e6d74 | 534 | .RB "$" " ls -l /proc/self/map_files/" |
18cdd0ac MK |
535 | lr\-\-\-\-\-\-\-\-. 1 root root 64 Apr 16 21:31 |
536 | 3252e00000\-3252e20000 \-> /usr/lib64/ld-2.15.so | |
b4f89985 PE |
537 | \&... |
538 | .fi | |
539 | .in | |
540 | ||
541 | Although these entries are present for memory regions that were | |
d6a56978 | 542 | mapped with the |
b4f89985 | 543 | .BR MAP_FILE |
18cdd0ac | 544 | flag, the way anonymous shared memory (regions created with the |
b4f89985 PE |
545 | .B MAP_ANON | MAP_SHARED |
546 | flags) | |
547 | is implemented in Linux | |
18cdd0ac MK |
548 | means that such regions also appear on this directory. |
549 | Here is an example where the target file is the deleted | |
550 | .I /dev/zero | |
551 | one: | |
b4f89985 PE |
552 | .in +4n |
553 | .nf | |
554 | ||
555 | .RB | |
18cdd0ac MK |
556 | lrw\-\-\-\-\-\-\-. 1 root root 64 Apr 16 21:33 |
557 | 7fc075d2f000\-7fc075e6f000 \-> /dev/zero (deleted) | |
b4f89985 PE |
558 | .fi |
559 | .in | |
560 | ||
561 | This directory appears only if the | |
562 | .B CONFIG_CHECKPOINT_RESTORE | |
563 | kernel configuration option is enabled. | |
fea681da | 564 | .TP |
69119dc7 | 565 | .I /proc/[pid]/maps |
fea681da MK |
566 | A file containing the currently mapped memory regions and their access |
567 | permissions. | |
bbf9f397 MK |
568 | See |
569 | .BR mmap (2) | |
570 | for some further information about memory mappings. | |
fea681da | 571 | |
dd0c3b96 | 572 | The format of the file is: |
fea681da | 573 | |
21781757 | 574 | .in -7n |
fea681da MK |
575 | .nf |
576 | .ft CW | |
fea681da | 577 | .ft |
21781757 MK |
578 | .I "address perms offset dev inode pathname" |
579 | 00400000-00452000 r-xp 00000000 08:02 173521 /usr/bin/dbus-daemon | |
580 | 00651000-00652000 r--p 00051000 08:02 173521 /usr/bin/dbus-daemon | |
581 | 00652000-00655000 rw-p 00052000 08:02 173521 /usr/bin/dbus-daemon | |
582 | 00e03000-00e24000 rw-p 00000000 00:00 0 [heap] | |
583 | 00e24000-011f7000 rw-p 00000000 00:00 0 [heap] | |
182090db | 584 | \&... |
21781757 MK |
585 | 35b1800000-35b1820000 r-xp 00000000 08:02 135522 /usr/lib64/ld-2.15.so |
586 | 35b1a1f000-35b1a20000 r--p 0001f000 08:02 135522 /usr/lib64/ld-2.15.so | |
587 | 35b1a20000-35b1a21000 rw-p 00020000 08:02 135522 /usr/lib64/ld-2.15.so | |
7d2e6d74 | 588 | 35b1a21000-35b1a22000 rw-p 00000000 00:00 0 |
21781757 MK |
589 | 35b1c00000-35b1dac000 r-xp 00000000 08:02 135870 /usr/lib64/libc-2.15.so |
590 | 35b1dac000-35b1fac000 ---p 001ac000 08:02 135870 /usr/lib64/libc-2.15.so | |
591 | 35b1fac000-35b1fb0000 r--p 001ac000 08:02 135870 /usr/lib64/libc-2.15.so | |
592 | 35b1fb0000-35b1fb2000 rw-p 001b0000 08:02 135870 /usr/lib64/libc-2.15.so | |
182090db | 593 | \&... |
21781757 | 594 | f2c6ff8c000-7f2c7078c000 rw-p 00000000 00:00 0 [stack:986] |
182090db | 595 | \&... |
21781757 MK |
596 | 7fffb2c0d000-7fffb2c2e000 rw-p 00000000 00:00 0 [stack] |
597 | 7fffb2d48000-7fffb2d49000 r-xp 00000000 00:00 0 [vdso] | |
fea681da | 598 | .fi |
21781757 | 599 | .in |
fea681da | 600 | |
7d2e6d74 | 601 | The |
3eb8c588 MK |
602 | .I address |
603 | field is the address space in the process that the mapping occupies. | |
604 | The | |
605 | .I perms | |
606 | field is a set of permissions: | |
fea681da MK |
607 | |
608 | .nf | |
609 | .in +5 | |
610 | r = read | |
611 | w = write | |
612 | x = execute | |
613 | s = shared | |
614 | p = private (copy on write) | |
615 | .fi | |
616 | .in | |
617 | ||
3eb8c588 MK |
618 | The |
619 | .I offset | |
b844cf04 | 620 | field is the offset into the file/whatever; |
3eb8c588 MK |
621 | .I dev |
622 | is the device | |
dd0c3b96 | 623 | (major:minor); |
3eb8c588 MK |
624 | .I inode |
625 | is the inode on that device. | |
59a40ed7 | 626 | 0 indicates that no inode is associated with the memory region, |
16e64bae | 627 | as would be the case with BSS (uninitialized data). |
fea681da | 628 | |
3eb8c588 MK |
629 | The |
630 | .I pathname | |
631 | field will usually be the file that is backing the mapping. | |
491ea6f1 | 632 | For ELF files, |
3eb8c588 MK |
633 | you can easily coordinate with the |
634 | .I offset | |
635 | field by looking at the | |
491ea6f1 MK |
636 | Offset field in the ELF program headers |
637 | .RI ( "readelf\ \-l" ). | |
37d32c38 | 638 | |
491ea6f1 | 639 | There are additional helpful pseudo-paths: |
61b0b1f4 MK |
640 | .RS 12 |
641 | .TP | |
642 | .IR [stack] | |
16e64bae | 643 | The initial process's (also known as the main thread's) stack. |
61b0b1f4 | 644 | .TP |
3eb8c588 | 645 | .IR [stack:<tid>] " (since Linux 3.4)" |
a60894c5 | 646 | .\" commit b76437579d1344b612cf1851ae610c636cec7db0 |
61b0b1f4 | 647 | A thread's stack (where the |
3eb8c588 | 648 | .IR <tid> |
61b0b1f4 | 649 | is a thread ID). |
491ea6f1 | 650 | It corresponds to the |
3eb8c588 | 651 | .IR /proc/[pid]/task/[tid]/ |
37d32c38 | 652 | path. |
61b0b1f4 | 653 | .TP |
7d2e6d74 | 654 | .IR [vdso] |
61b0b1f4 MK |
655 | The virtual dynamically linked shared object. |
656 | .TP | |
7d2e6d74 | 657 | .IR [heap] |
61b0b1f4 MK |
658 | The process's heap. |
659 | .in | |
61b0b1f4 MK |
660 | .RE |
661 | .IP | |
3eb8c588 MK |
662 | If the |
663 | .I pathname | |
664 | field is blank, | |
491ea6f1 | 665 | this is an anonymous mapping as obtained via the |
37d32c38 | 666 | .BR mmap (2) |
491ea6f1 | 667 | function. |
61b0b1f4 MK |
668 | There is no easy way to coordinate this back to a process's source, |
669 | short of running it through | |
491ea6f1 MK |
670 | .BR gdb (1), |
671 | .BR strace (1), | |
672 | or similar. | |
37d32c38 | 673 | |
fea681da MK |
674 | Under Linux 2.0 there is no field giving pathname. |
675 | .TP | |
69119dc7 | 676 | .I /proc/[pid]/mem |
fea681da MK |
677 | This file can be used to access the pages of a process's memory through |
678 | .BR open (2), | |
679 | .BR read (2), | |
680 | and | |
ccb2bb0d | 681 | .BR lseek (2). |
b4e9ee8f | 682 | .TP |
69119dc7 | 683 | .IR /proc/[pid]/mountinfo " (since Linux 2.6.26)" |
b4e9ee8f MK |
684 | .\" This info adapted from Documentation/filesystems/proc.txt |
685 | This file contains information about mount points. | |
686 | It contains lines of the form: | |
687 | .nf | |
688 | .ft CW | |
b4e9ee8f MK |
689 | |
690 | 36 35 98:0 /mnt1 /mnt2 rw,noatime master:1 - ext3 /dev/root rw,errors=continue | |
691 | (1)(2)(3) (4) (5) (6) (7) (8) (9) (10) (11) | |
b4e9ee8f MK |
692 | .ft |
693 | .fi | |
694 | .IP | |
695 | The numbers in parentheses are labels for the descriptions below: | |
3bc960c2 | 696 | .RS 7 |
b4e9ee8f MK |
697 | .TP 5 |
698 | (1) | |
699 | mount ID: unique identifier of the mount (may be reused after | |
700 | .BR umount (2)). | |
701 | .TP | |
702 | (2) | |
703 | parent ID: ID of parent mount (or of self for the top of the mount tree). | |
704 | .TP | |
705 | (3) | |
706 | major:minor: value of | |
707 | .I st_dev | |
9ee4a2b6 | 708 | for files on filesystem (see |
b4e9ee8f MK |
709 | .BR stat (2)). |
710 | .TP | |
711 | (4) | |
9ee4a2b6 | 712 | root: root of the mount within the filesystem. |
b4e9ee8f MK |
713 | .TP |
714 | (5) | |
715 | mount point: mount point relative to the process's root. | |
716 | .TP | |
717 | (6) | |
718 | mount options: per-mount options. | |
719 | .TP | |
720 | (7) | |
721 | optional fields: zero or more fields of the form "tag[:value]". | |
722 | .TP | |
723 | (8) | |
724 | separator: marks the end of the optional fields. | |
725 | .TP | |
726 | (9) | |
9ee4a2b6 | 727 | filesystem type: name of filesystem in the form "type[.subtype]". |
b4e9ee8f MK |
728 | .TP |
729 | (10) | |
9ee4a2b6 | 730 | mount source: filesystem-specific information or "none". |
b4e9ee8f MK |
731 | .TP |
732 | (11) | |
68d86eac | 733 | super options: per-superblock options. |
b4e9ee8f MK |
734 | .RE |
735 | .IP | |
736 | Parsers should ignore all unrecognized optional fields. | |
737 | Currently the possible optional fields are: | |
738 | .RS 12 | |
739 | .TP 18 | |
740 | shared:X | |
741 | mount is shared in peer group X | |
742 | .TP | |
743 | master:X | |
744 | mount is slave to peer group X | |
745 | .TP | |
746 | propagate_from:X | |
747 | mount is slave and receives propagation from peer group X (*) | |
748 | .TP | |
749 | unbindable | |
750 | mount is unbindable | |
751 | .RE | |
752 | .IP | |
753 | (*) X is the closest dominant peer group under the process's root. | |
754 | If X is the immediate master of the mount, | |
755 | or if there is no dominant peer group under the same root, | |
756 | then only the "master:X" field is present | |
757 | and not the "propagate_from:X" field. | |
758 | ||
759 | For more information on mount propagation see: | |
760 | .I Documentation/filesystems/sharedsubtree.txt | |
66a9882e | 761 | in the Linux kernel source tree. |
b4e9ee8f | 762 | .TP |
cea61382 | 763 | .IR /proc/[pid]/mounts " (since Linux 2.4.19)" |
9ee4a2b6 | 764 | This is a list of all the filesystems currently mounted in the |
732e54dd | 765 | process's mount namespace. |
cea61382 MK |
766 | The format of this file is documented in |
767 | .BR fstab (5). | |
768 | Since kernel version 2.6.15, this file is pollable: | |
769 | after opening the file for reading, a change in this file | |
9ee4a2b6 | 770 | (i.e., a filesystem mount or unmount) causes |
cea61382 MK |
771 | .BR select (2) |
772 | to mark the file descriptor as readable, and | |
773 | .BR poll (2) | |
774 | and | |
775 | .BR epoll_wait (2) | |
776 | mark the file as having an error condition. | |
777 | .TP | |
69119dc7 | 778 | .IR /proc/[pid]/mountstats " (since Linux 2.6.17)" |
783a6233 | 779 | This file exports information (statistics, configuration information) |
b4e9ee8f MK |
780 | about the mount points in the process's name space. |
781 | Lines in this file have the form: | |
782 | .nf | |
783 | ||
784 | device /dev/sda7 mounted on /home with fstype ext3 [statistics] | |
785 | ( 1 ) ( 2 ) (3 ) (4) | |
786 | .fi | |
787 | .IP | |
788 | The fields in each line are: | |
3bc960c2 | 789 | .RS 7 |
b4e9ee8f MK |
790 | .TP 5 |
791 | (1) | |
792 | The name of the mounted device | |
793 | (or "nodevice" if there is no corresponding device). | |
794 | .TP | |
795 | (2) | |
9ee4a2b6 | 796 | The mount point within the filesystem tree. |
b4e9ee8f MK |
797 | .TP |
798 | (3) | |
9ee4a2b6 | 799 | The filesystem type. |
b4e9ee8f MK |
800 | .TP |
801 | (4) | |
802 | Optional statistics and configuration information. | |
9ee4a2b6 | 803 | Currently (as at Linux 2.6.26), only NFS filesystems export |
b4e9ee8f MK |
804 | information via this field. |
805 | .RE | |
806 | .IP | |
90878f7c | 807 | This file is readable only by the owner of the process. |
b4e9ee8f | 808 | .TP |
b4a185e5 | 809 | .IR /proc/[pid]/ns/ " (since Linux 3.0)" |
2c4201f0 | 810 | .\" See commit 6b4e306aa3dc94a0545eb9279475b1ab6209a31f |
b4a185e5 EB |
811 | This is a subdirectory containing one entry for each namespace that |
812 | supports being manipulated by | |
80e63655 MK |
813 | .BR setns (2). |
814 | For information about namespaces, see | |
815 | .BR clone (2). | |
b4a185e5 EB |
816 | .TP |
817 | .IR /proc/[pid]/ns/ipc " (since Linux 3.0)" | |
80e63655 MK |
818 | Bind mounting this file (see |
819 | .BR mount (2)) | |
820 | to somewhere else in the filesystem keeps | |
c409c4ff | 821 | the IPC namespace of the process specified by |
b4a185e5 | 822 | .I pid |
80e63655 | 823 | alive even if all processes currently in the namespace terminate. |
b4a185e5 | 824 | |
80e63655 | 825 | Opening this file returns a file handle for the IPC namespace |
b4a185e5 | 826 | of the process specified by |
80e63655 MK |
827 | .IR pid . |
828 | As long as this file descriptor remains open, | |
829 | the IPC namespace will remain alive, | |
830 | even if all processes in the namespace terminate. | |
831 | The file descriptor can be passed to | |
832 | .BR setns (2). | |
b4a185e5 EB |
833 | .TP |
834 | .IR /proc/[pid]/ns/net " (since Linux 3.0)" | |
80e63655 MK |
835 | Bind mounting this file (see |
836 | .BR mount (2)) | |
837 | to somewhere else in the filesystem keeps | |
c409c4ff | 838 | the network namespace of the process specified by |
b4a185e5 | 839 | .I pid |
80e63655 | 840 | alive even if all processes in the namespace terminate. |
b4a185e5 | 841 | |
80e63655 | 842 | Opening this file returns a file handle for the network namespace |
b4a185e5 | 843 | of the process specified by |
80e63655 MK |
844 | .IR pid . |
845 | As long as this file descriptor remains open, | |
846 | the network namespace will remain alive, | |
847 | even if all processes in the namespace terminate. | |
848 | The file descriptor can be passed to | |
849 | .BR setns (2). | |
b4a185e5 EB |
850 | .TP |
851 | .IR /proc/[pid]/ns/uts " (since Linux 3.0)" | |
80e63655 MK |
852 | Bind mounting this file (see |
853 | .BR mount (2)) | |
854 | to somewhere else in the filesystem keeps | |
c409c4ff | 855 | the UTS namespace of the process specified by |
b4a185e5 | 856 | .I pid |
80e63655 | 857 | alive even if all processes currently in the namespace terminate. |
b4a185e5 | 858 | |
80e63655 | 859 | Opening this file returns a file handle for the UTS namespace |
b4a185e5 | 860 | of the process specified by |
80e63655 MK |
861 | .IR pid . |
862 | As long as this file descriptor remains open, | |
863 | the UTS namespace will remain alive, | |
864 | even if all processes in the namespace terminate. | |
865 | The file descriptor can be passed to | |
866 | .BR setns (2). | |
b4a185e5 | 867 | .TP |
69119dc7 | 868 | .IR /proc/[pid]/numa_maps " (since Linux 2.6.14)" |
610f75cc MK |
869 | See |
870 | .BR numa (7). | |
7388733a | 871 | .TP |
69119dc7 | 872 | .IR /proc/[pid]/oom_adj " (since Linux 2.6.11)" |
b4e9ee8f | 873 | This file can be used to adjust the score used to select which process |
0425de01 | 874 | should be killed in an out-of-memory (OOM) situation. |
b4e9ee8f MK |
875 | The kernel uses this value for a bit-shift operation of the process's |
876 | .IR oom_score | |
877 | value: | |
5b8dbfd4 MK |
878 | valid values are in the range \-16 to +15, |
879 | plus the special value \-17, | |
b4e9ee8f MK |
880 | which disables OOM-killing altogether for this process. |
881 | A positive score increases the likelihood of this | |
882 | process being killed by the OOM-killer; | |
883 | a negative score decreases the likelihood. | |
de8e9cc1 | 884 | .IP |
b4e9ee8f MK |
885 | The default value for this file is 0; |
886 | a new process inherits its parent's | |
887 | .I oom_adj | |
888 | setting. | |
889 | A process must be privileged | |
890 | .RB ( CAP_SYS_RESOURCE ) | |
891 | to update this file. | |
f2c8b197 MK |
892 | .IP |
893 | Since Linux 2.6.36, use of this file is deprecated in favor of | |
894 | .IR /proc/[pid]/oom_score_adj . | |
b4e9ee8f | 895 | .TP |
69119dc7 | 896 | .IR /proc/[pid]/oom_score " (since Linux 2.6.11)" |
b4e9ee8f MK |
897 | .\" See mm/oom_kill.c::badness() in the 2.6.25 sources |
898 | This file displays the current score that the kernel gives to | |
899 | this process for the purpose of selecting a process | |
900 | for the OOM-killer. | |
901 | A higher score means that the process is more likely to be | |
902 | selected by the OOM-killer. | |
903 | The basis for this score is the amount of memory used by the process, | |
904 | with increases (+) or decreases (\-) for factors including: | |
905 | .\" See mm/oom_kill.c::badness() in the 2.6.25 sources | |
906 | .RS | |
907 | .IP * 2 | |
908 | whether the process creates a lot of children using | |
909 | .BR fork (2) | |
910 | (+); | |
911 | .IP * | |
912 | whether the process has been running a long time, | |
913 | or has used a lot of CPU time (\-); | |
914 | .IP * | |
915 | whether the process has a low nice value (i.e., > 0) (+); | |
916 | .IP * | |
917 | whether the process is privileged (\-); and | |
918 | .\" More precisely, if it has CAP_SYS_ADMIN or CAP_SYS_RESOURCE | |
919 | .IP * | |
920 | whether the process is making direct hardware access (\-). | |
921 | .\" More precisely, if it has CAP_SYS_RAWIO | |
922 | .RE | |
923 | .IP | |
924 | The | |
925 | .I oom_score | |
f2c8b197 MK |
926 | also reflects the adjustment specified by the |
927 | .I oom_score_adj | |
928 | or | |
b4e9ee8f MK |
929 | .I oom_adj |
930 | setting for the process. | |
f2c8b197 MK |
931 | .TP |
932 | .IR /proc/[pid]/oom_score_adj " (since Linux 2.6.36)" | |
933 | .\" Text taken from 3.7 Documentation/filesystems/proc.txt | |
934 | This file can be used to adjust the badness heuristic used to select which | |
935 | process gets killed in out-of-memory conditions. | |
936 | ||
937 | The badness heuristic assigns a value to each candidate task ranging from 0 | |
938 | (never kill) to 1000 (always kill) to determine which process is targeted. | |
939 | The units are roughly a proportion along that range of | |
940 | allowed memory the process may allocate from, | |
941 | based on an estimation of its current memory and swap use. | |
942 | For example, if a task is using all allowed memory, | |
943 | its badness score will be 1000. | |
944 | If it is using half of its allowed memory, its score will be 500. | |
945 | ||
946 | There is an additional factor included in the badness score: root | |
947 | processes are given 3% extra memory over other tasks. | |
948 | ||
949 | The amount of "allowed" memory depends on the context | |
0633f951 | 950 | in which the OOM-killer was called. |
f2c8b197 MK |
951 | If it is due to the memory assigned to the allocating task's cpuset |
952 | being exhausted, | |
953 | the allowed memory represents the set of mems assigned to that | |
954 | cpuset (see | |
955 | .BR cpuset (7)). | |
956 | If it is due to a mempolicy's node(s) being exhausted, | |
957 | the allowed memory represents the set of mempolicy nodes. | |
958 | If it is due to a memory limit (or swap limit) being reached, | |
959 | the allowed memory is that configured limit. | |
960 | Finally, if it is due to the entire system being out of memory, the | |
961 | allowed memory represents all allocatable resources. | |
962 | ||
963 | The value of | |
0633f951 | 964 | .I oom_score_adj |
f2c8b197 MK |
965 | is added to the badness score before it |
966 | is used to determine which task to kill. | |
967 | Acceptable values range from \-1000 | |
968 | (OOM_SCORE_ADJ_MIN) to +1000 (OOM_SCORE_ADJ_MAX). | |
0633f951 | 969 | This allows user space to control the preference for OOM-killing, |
f2c8b197 | 970 | ranging from always preferring a certain |
0633f951 | 971 | task or completely disabling it from OOM-killing. |
f2c8b197 | 972 | The lowest possible value, \-1000, is |
0633f951 | 973 | equivalent to disabling OOM-killing entirely for that task, |
f2c8b197 MK |
974 | since it will always report a badness score of 0. |
975 | ||
976 | Consequently, it is very simple for user space to define | |
977 | the amount of memory to consider for each task. | |
978 | Setting a | |
979 | .I oom_score_adj | |
980 | value of +500, for example, | |
981 | is roughly equivalent to allowing the remainder of tasks sharing the | |
982 | same system, cpuset, mempolicy, or memory controller resources | |
983 | to use at least 50% more memory. | |
984 | A value of \-500, on the other hand, would be roughly | |
985 | equivalent to discounting 50% of the task's | |
986 | allowed memory from being considered as scoring against the task. | |
987 | ||
0633f951 | 988 | For backward compatibility with previous kernels, |
f2c8b197 MK |
989 | .I /proc/[pid]/oom_adj |
990 | can still be used to tune the badness score. | |
991 | Its value is | |
9f1b9726 | 992 | scaled linearly with |
f2c8b197 MK |
993 | .IR oom_score_adj . |
994 | ||
995 | Writing to | |
996 | .IR /proc/[pid]/oom_score_adj | |
997 | or | |
998 | .IR /proc/[pid]/oom_adj | |
999 | will change the other with its scaled value. | |
69119dc7 | 1000 | .\" FIXME Describe /proc/[pid]/pagemap |
b4e9ee8f MK |
1001 | .\" Added in 2.6.25 |
1002 | .\" CONFIG_PROC_PAGE_MONITOR | |
fea681da | 1003 | .TP |
69119dc7 | 1004 | .I /proc/[pid]/root |
008f1ecc | 1005 | UNIX and Linux support the idea of a per-process root of the |
9ee4a2b6 | 1006 | filesystem, set by the |
fea681da | 1007 | .BR chroot (2) |
c13182ef MK |
1008 | system call. |
1009 | This file is a symbolic link that points to the process's | |
14d70713 MK |
1010 | root directory, and behaves in the same way as |
1011 | .IR exe , | |
1012 | and | |
1013 | .IR fd/* . | |
afcaf646 MK |
1014 | |
1015 | .\" The following was still true as at kernel 2.6.13 | |
c13182ef MK |
1016 | In a multithreaded process, the contents of this symbolic link |
1017 | are not available if the main thread has already terminated | |
afcaf646 MK |
1018 | (typically by calling |
1019 | .BR pthread_exit (3)). | |
69119dc7 | 1020 | .\" FIXME Describe /proc/[pid]/seccomp |
6aefb6df | 1021 | .\" Added in 2.6.12 |
69119dc7 | 1022 | .\" FIXME Describe /proc/[pid]/sessionid |
b4e9ee8f MK |
1023 | .\" Added in 2.6.25; read-only; only readable by real UID |
1024 | .\" CONFIG_AUDITSYSCALL | |
69119dc7 | 1025 | .\" FIXME Describe /proc/[pid]/sched |
b4e9ee8f MK |
1026 | .\" Added in 2.6.23 |
1027 | .\" CONFIG_SCHED_DEBUG, and additional fields if CONFIG_SCHEDSTATS | |
1028 | .\" Displays various scheduling parameters | |
1029 | .\" This file can be written, to reset stats | |
69119dc7 MK |
1030 | .\" FIXME Describe /proc/[pid]/schedstats and |
1031 | .\" /proc/[pid]/task/[tid]/schedstats | |
b4e9ee8f MK |
1032 | .\" Added in 2.6.9 |
1033 | .\" CONFIG_SCHEDSTATS | |
fea681da | 1034 | .TP |
69119dc7 | 1035 | .IR /proc/[pid]/smaps " (since Linux 2.6.14)" |
b07b19c4 | 1036 | This file shows memory consumption for each of the process's mappings. |
1f0add28 | 1037 | For each mapping there is a series of lines such as the following: |
a08ea57c | 1038 | .in +4n |
b07b19c4 MK |
1039 | .nf |
1040 | ||
1f0add28 | 1041 | 00400000-0048a000 r-xp 00000000 fd:03 960637 /bin/bash |
95fe794d PG |
1042 | Size: 552 kB |
1043 | Rss: 460 kB | |
1044 | Pss: 100 kB | |
1045 | Shared_Clean: 452 kB | |
1046 | Shared_Dirty: 0 kB | |
1047 | Private_Clean: 8 kB | |
1048 | Private_Dirty: 0 kB | |
1049 | Referenced: 460 kB | |
1050 | Anonymous: 0 kB | |
1051 | AnonHugePages: 0 kB | |
1052 | Swap: 0 kB | |
1053 | KernelPageSize: 4 kB | |
1054 | MMUPageSize: 4 kB | |
1055 | Locked: 0 kB | |
b07b19c4 MK |
1056 | |
1057 | .fi | |
a08ea57c | 1058 | .in |
b07b19c4 MK |
1059 | The first of these lines shows the same information as is displayed |
1060 | for the mapping in | |
69119dc7 | 1061 | .IR /proc/[pid]/maps . |
b07b19c4 | 1062 | The remaining lines show the size of the mapping, |
95fe794d PG |
1063 | the amount of the mapping that is currently resident in RAM ("Rss"), |
1064 | the process' proportional share of this mapping ("Pss"), | |
1f0add28 | 1065 | the number of clean and dirty shared pages in the mapping, |
c7ce200d | 1066 | and the number of clean and dirty private pages in the mapping. |
95fe794d | 1067 | "Referenced" indicates the amount of memory currently marked as |
1f0add28 MK |
1068 | referenced or accessed. |
1069 | "Anonymous" shows the amount of memory | |
1070 | that does not belong to any file. | |
1071 | "Swap" shows how much | |
95fe794d PG |
1072 | would-be-anonymous memory is also used, but out on swap. |
1073 | ||
d6a56978 | 1074 | The "KernelPageSize" entry is the page size used by the kernel to back a VMA. |
1f0add28 MK |
1075 | This matches the size used by the MMU in the majority of cases. |
1076 | However, one counter-example occurs on PPC64 kernels | |
1077 | whereby a kernel using 64K as a base page size may still use 4K | |
1078 | pages for the MMU on older processors. | |
1079 | To distinguish, this | |
1080 | patch reports "MMUPageSize" as the page size used by the MMU. | |
95fe794d PG |
1081 | |
1082 | The "Locked" indicates whether the mapping is locked in memory | |
1083 | or not. | |
1084 | ||
1085 | "VmFlags" field represents the kernel flags associated with | |
1f0add28 MK |
1086 | the particular virtual memory area in two letter encoded manner. |
1087 | The codes are the following: | |
1088 | ||
95fe794d | 1089 | rd - readable |
1f0add28 | 1090 | wr - writable |
95fe794d PG |
1091 | ex - executable |
1092 | sh - shared | |
1093 | mr - may read | |
1094 | mw - may write | |
1095 | me - may execute | |
1096 | ms - may share | |
723e333c | 1097 | gd - stack segment grows down |
95fe794d PG |
1098 | pf - pure PFN range |
1099 | dw - disabled write to the mapped file | |
1100 | lo - pages are locked in memory | |
1101 | io - memory mapped I/O area | |
1102 | sr - sequential read advise provided | |
1103 | rr - random read advise provided | |
1104 | dc - do not copy area on fork | |
1105 | de - do not expand area on remapping | |
1106 | ac - area is accountable | |
1107 | nr - swap space is not reserved for the area | |
1108 | ht - area uses huge tlb pages | |
1109 | nl - non-linear mapping | |
1110 | ar - architecture specific flag | |
1111 | dd - do not include area into core dump | |
1112 | sd - soft-dirty flag | |
1113 | mm - mixed map area | |
1114 | hg - huge page advise flag | |
1115 | nh - no-huge page advise flag | |
b5408a0f | 1116 | mg - mergeable advise flag |
b07b19c4 | 1117 | |
e618d945 MK |
1118 | The |
1119 | .IR /proc/[pid]/smaps | |
1120 | file is present only if the | |
1121 | .B CONFIG_PROC_PAGE_MONITOR | |
1122 | kernel configuration option is enabled. | |
b07b19c4 | 1123 | .TP |
67aac6fb MK |
1124 | .IR /proc/[pid]/stack " (since Linux 2.6.29)" |
1125 | .\" 2ec220e27f5040aec1e88901c1b6ea3d135787ad | |
1126 | This file provides a symbolic trace of the function calls in this | |
1127 | process's kernel stack. | |
1128 | This file is provided only if the kernel was built with the | |
1129 | .B CONFIG_STACKTRACE | |
1130 | configuration option. | |
1131 | .TP | |
69119dc7 | 1132 | .I /proc/[pid]/stat |
c13182ef MK |
1133 | Status information about the process. |
1134 | This is used by | |
1135 | .BR ps (1). | |
1136 | It is defined in | |
fea681da MK |
1137 | .IR /usr/src/linux/fs/proc/array.c "." |
1138 | ||
1139 | The fields, in order, with their proper | |
1140 | .BR scanf (3) | |
1141 | format specifiers, are: | |
1142 | .RS | |
59a40ed7 | 1143 | .TP 12 |
fea681da | 1144 | \fIpid\fP %d |
aa610245 | 1145 | (1) The process ID. |
fea681da MK |
1146 | .TP |
1147 | \fIcomm\fP %s | |
aa610245 | 1148 | (2) The filename of the executable, in parentheses. |
c13182ef | 1149 | This is visible whether or not the executable is swapped out. |
fea681da MK |
1150 | .TP |
1151 | \fIstate\fP %c | |
aa610245 | 1152 | (3) One character from the string "RSDZTW" where R is running, S is |
fea681da MK |
1153 | sleeping in an interruptible wait, D is waiting in uninterruptible |
1154 | disk sleep, Z is zombie, T is traced or stopped (on a signal), | |
1155 | and W is paging. | |
1156 | .TP | |
1157 | \fIppid\fP %d | |
aa610245 | 1158 | (4) The PID of the parent. |
fea681da MK |
1159 | .TP |
1160 | \fIpgrp\fP %d | |
aa610245 | 1161 | (5) The process group ID of the process. |
fea681da MK |
1162 | .TP |
1163 | \fIsession\fP %d | |
aa610245 | 1164 | (6) The session ID of the process. |
fea681da | 1165 | .TP |
fea681da | 1166 | \fItty_nr\fP %d |
aa610245 | 1167 | (7) The controlling terminal of the process. |
59a40ed7 MK |
1168 | (The minor device number is contained in the combination of bits |
1169 | 31 to 20 and 7 to 0; | |
b97deb97 | 1170 | the major device number is in bits 15 to 8.) |
fea681da MK |
1171 | .TP |
1172 | \fItpgid\fP %d | |
1173 | .\" This field and following, up to and including wchan added 0.99.1 | |
aa610245 | 1174 | (8) The ID of the foreground process group of the controlling |
59a40ed7 | 1175 | terminal of the process. |
fea681da | 1176 | .TP |
2ebfeb1b | 1177 | \fIflags\fP %u (%lu before Linux 2.6.22) |
aa610245 | 1178 | (9) The kernel flags word of the process. |
c13182ef | 1179 | For bit meanings, |
66a9882e | 1180 | see the PF_* defines in the Linux kernel source file |
00702acc | 1181 | .IR include/linux/sched.h . |
fea681da MK |
1182 | Details depend on the kernel version. |
1183 | .TP | |
1184 | \fIminflt\fP %lu | |
aa610245 | 1185 | (10) The number of minor faults the process has made which have not |
fea681da MK |
1186 | required loading a memory page from disk. |
1187 | .TP | |
1188 | \fIcminflt\fP %lu | |
aa610245 | 1189 | (11) The number of minor faults that the process's |
fea681da MK |
1190 | waited-for children have made. |
1191 | .TP | |
1192 | \fImajflt\fP %lu | |
aa610245 | 1193 | (12) The number of major faults the process has made which have |
fea681da MK |
1194 | required loading a memory page from disk. |
1195 | .TP | |
1196 | \fIcmajflt\fP %lu | |
aa610245 | 1197 | (13) The number of major faults that the process's |
fea681da MK |
1198 | waited-for children have made. |
1199 | .TP | |
1200 | \fIutime\fP %lu | |
aa610245 | 1201 | (14) Amount of time that this process has been scheduled in user mode, |
7a017e24 | 1202 | measured in clock ticks (divide by |
67914165 | 1203 | .IR sysconf(_SC_CLK_TCK) ). |
a1c9dc59 MK |
1204 | This includes guest time, \fIguest_time\fP |
1205 | (time spent running a virtual CPU, see below), | |
1206 | so that applications that are not aware of the guest time field | |
1207 | do not lose that time from their calculations. | |
fea681da MK |
1208 | .TP |
1209 | \fIstime\fP %lu | |
aa610245 | 1210 | (15) Amount of time that this process has been scheduled in kernel mode, |
7a017e24 | 1211 | measured in clock ticks (divide by |
67914165 | 1212 | .IR sysconf(_SC_CLK_TCK) ). |
fea681da MK |
1213 | .TP |
1214 | \fIcutime\fP %ld | |
aa610245 | 1215 | (16) Amount of time that this process's |
7a017e24 MK |
1216 | waited-for children have been scheduled in user mode, |
1217 | measured in clock ticks (divide by | |
67914165 | 1218 | .IR sysconf(_SC_CLK_TCK) ). |
c13182ef | 1219 | (See also |
fea681da | 1220 | .BR times (2).) |
a1c9dc59 MK |
1221 | This includes guest time, \fIcguest_time\fP |
1222 | (time spent running a virtual CPU, see below). | |
fea681da MK |
1223 | .TP |
1224 | \fIcstime\fP %ld | |
aa610245 | 1225 | (17) Amount of time that this process's |
7a017e24 MK |
1226 | waited-for children have been scheduled in kernel mode, |
1227 | measured in clock ticks (divide by | |
67914165 | 1228 | .IR sysconf(_SC_CLK_TCK) ). |
fea681da MK |
1229 | .TP |
1230 | \fIpriority\fP %ld | |
aa610245 | 1231 | (18) (Explanation for Linux 2.6) |
59a40ed7 MK |
1232 | For processes running a real-time scheduling policy |
1233 | .RI ( policy | |
1234 | below; see | |
1235 | .BR sched_setscheduler (2)), | |
1236 | this is the negated scheduling priority, minus one; | |
1237 | that is, a number in the range \-2 to \-100, | |
1238 | corresponding to real-time priorities 1 to 99. | |
1239 | For processes running under a non-real-time scheduling policy, | |
1240 | this is the raw nice value | |
1241 | .RB ( setpriority (2)) | |
1242 | as represented in the kernel. | |
1243 | The kernel stores nice values as numbers | |
1244 | in the range 0 (high) to 39 (low), | |
1245 | corresponding to the user-visible nice range of \-20 to 19. | |
1246 | ||
1247 | Before Linux 2.6, this was a scaled value based on | |
1248 | the scheduler weighting given to this process. | |
1249 | .\" And back in kernel 1.2 days things were different again. | |
fea681da MK |
1250 | .TP |
1251 | \fInice\fP %ld | |
aa610245 | 1252 | (19) The nice value (see |
59a40ed7 MK |
1253 | .BR setpriority (2)), |
1254 | a value in the range 19 (low priority) to \-20 (high priority). | |
1255 | .\" Back in kernel 1.2 days things were different. | |
fea681da MK |
1256 | .\" .TP |
1257 | .\" \fIcounter\fP %ld | |
1258 | .\" The current maximum size in jiffies of the process's next timeslice, | |
1259 | .\" or what is currently left of its current timeslice, if it is the | |
1260 | .\" currently running process. | |
1261 | .\" .TP | |
1262 | .\" \fItimeout\fP %u | |
1263 | .\" The time in jiffies of the process's next timeout. | |
0e94f77b | 1264 | .\" timeout was removed sometime around 2.1/2.2 |
aa610245 | 1265 | .TP |
0e94f77b | 1266 | \fInum_threads\fP %ld |
aa610245 | 1267 | (20) Number of threads in this process (since Linux 2.6). |
bb83d1b9 | 1268 | Before kernel 2.6, this field was hard coded to 0 as a placeholder |
0e94f77b | 1269 | for an earlier removed field. |
fea681da MK |
1270 | .TP |
1271 | \fIitrealvalue\fP %ld | |
aa610245 | 1272 | (21) The time in jiffies before the next |
8bd58774 MK |
1273 | .B SIGALRM |
1274 | is sent to the process due to an interval timer. | |
0e94f77b MK |
1275 | Since kernel 2.6.17, this field is no longer maintained, |
1276 | and is hard coded as 0. | |
fea681da | 1277 | .TP |
0e94f77b | 1278 | \fIstarttime\fP %llu (was %lu before Linux 2.6) |
aa610245 | 1279 | (22) The time the process started after system boot. |
055024ed MK |
1280 | In kernels before Linux 2.6, this value was expressed in jiffies. |
1281 | Since Linux 2.6, the value is expressed in clock ticks (divide by | |
1282 | .IR sysconf(_SC_CLK_TCK) ). | |
fea681da MK |
1283 | .TP |
1284 | \fIvsize\fP %lu | |
aa610245 | 1285 | (23) Virtual memory size in bytes. |
fea681da MK |
1286 | .TP |
1287 | \fIrss\fP %ld | |
aa610245 | 1288 | (24) Resident Set Size: number of pages the process has in real memory. |
c13182ef | 1289 | This is just the pages which |
5fab2e7c | 1290 | count toward text, data, or stack space. |
c13182ef | 1291 | This does not include pages |
fea681da MK |
1292 | which have not been demand-loaded in, or which are swapped out. |
1293 | .TP | |
59a40ed7 | 1294 | \fIrsslim\fP %lu |
aa610245 | 1295 | (25) Current soft limit in bytes on the rss of the process; |
59a40ed7 MK |
1296 | see the description of |
1297 | .B RLIMIT_RSS | |
1298 | in | |
2b5407af | 1299 | .BR getrlimit (2). |
fea681da MK |
1300 | .TP |
1301 | \fIstartcode\fP %lu | |
aa610245 | 1302 | (26) The address above which program text can run. |
fea681da MK |
1303 | .TP |
1304 | \fIendcode\fP %lu | |
aa610245 | 1305 | (27) The address below which program text can run. |
fea681da MK |
1306 | .TP |
1307 | \fIstartstack\fP %lu | |
aa610245 | 1308 | (28) The address of the start (i.e., bottom) of the stack. |
fea681da MK |
1309 | .TP |
1310 | \fIkstkesp\fP %lu | |
aa610245 | 1311 | (29) The current value of ESP (stack pointer), as found in the |
fea681da MK |
1312 | kernel stack page for the process. |
1313 | .TP | |
1314 | \fIkstkeip\fP %lu | |
aa610245 | 1315 | (30) The current EIP (instruction pointer). |
fea681da MK |
1316 | .TP |
1317 | \fIsignal\fP %lu | |
aa610245 | 1318 | (31) The bitmap of pending signals, displayed as a decimal number. |
59a40ed7 | 1319 | Obsolete, because it does not provide information on real-time signals; use |
69119dc7 | 1320 | .I /proc/[pid]/status |
59a40ed7 | 1321 | instead. |
fea681da MK |
1322 | .TP |
1323 | \fIblocked\fP %lu | |
aa610245 | 1324 | (32) The bitmap of blocked signals, displayed as a decimal number. |
59a40ed7 | 1325 | Obsolete, because it does not provide information on real-time signals; use |
69119dc7 | 1326 | .I /proc/[pid]/status |
59a40ed7 | 1327 | instead. |
fea681da MK |
1328 | .TP |
1329 | \fIsigignore\fP %lu | |
aa610245 | 1330 | (33) The bitmap of ignored signals, displayed as a decimal number. |
59a40ed7 | 1331 | Obsolete, because it does not provide information on real-time signals; use |
69119dc7 | 1332 | .I /proc/[pid]/status |
59a40ed7 | 1333 | instead. |
fea681da MK |
1334 | .TP |
1335 | \fIsigcatch\fP %lu | |
aa610245 | 1336 | (34) The bitmap of caught signals, displayed as a decimal number. |
59a40ed7 | 1337 | Obsolete, because it does not provide information on real-time signals; use |
69119dc7 | 1338 | .I /proc/[pid]/status |
59a40ed7 | 1339 | instead. |
fea681da MK |
1340 | .TP |
1341 | \fIwchan\fP %lu | |
aa610245 | 1342 | (35) This is the "channel" in which the process is waiting. |
2054f761 MK |
1343 | It is the address of a location in the kernel where the process is sleeping. |
1344 | The corresponding symbolic name can be found in | |
1345 | .IR /proc/[pid]/wchan . | |
fea681da MK |
1346 | .TP |
1347 | \fInswap\fP %lu | |
0633f951 DP |
1348 | (36) |
1349 | .\" nswap was added in 2.0 | |
4d9b6984 | 1350 | Number of pages swapped (not maintained). |
fea681da MK |
1351 | .TP |
1352 | \fIcnswap\fP %lu | |
0633f951 DP |
1353 | (37) |
1354 | .\" cnswap was added in 2.0 | |
4d9b6984 | 1355 | Cumulative \fInswap\fP for child processes (not maintained). |
fea681da | 1356 | .TP |
2ebfeb1b | 1357 | \fIexit_signal\fP %d (since Linux 2.1.22) |
aa610245 | 1358 | (38) Signal to be sent to parent when we die. |
fea681da | 1359 | .TP |
2ebfeb1b | 1360 | \fIprocessor\fP %d (since Linux 2.2.8) |
aa610245 | 1361 | (39) CPU number last executed on. |
568105c6 | 1362 | .TP |
2ebfeb1b | 1363 | \fIrt_priority\fP %u (since Linux 2.5.19; was %lu before Linux 2.6.22) |
aa610245 | 1364 | (40) Real-time scheduling priority, a number in the range 1 to 99 for |
59a40ed7 MK |
1365 | processes scheduled under a real-time policy, |
1366 | or 0, for non-real-time processes (see | |
568105c6 MK |
1367 | .BR sched_setscheduler (2)). |
1368 | .TP | |
2ebfeb1b | 1369 | \fIpolicy\fP %u (since Linux 2.5.19; was %lu before Linux 2.6.22) |
aa610245 | 1370 | (41) Scheduling policy (see |
568105c6 | 1371 | .BR sched_setscheduler (2)). |
cd60dedd | 1372 | Decode using the SCHED_* constants in |
59a40ed7 | 1373 | .IR linux/sched.h . |
167450d6 | 1374 | .TP |
2ebfeb1b | 1375 | \fIdelayacct_blkio_ticks\fP %llu (since Linux 2.6.18) |
aa610245 | 1376 | (42) Aggregated block I/O delays, measured in clock ticks (centiseconds). |
14c06953 MK |
1377 | .TP |
1378 | \fIguest_time\fP %lu (since Linux 2.6.24) | |
aa610245 | 1379 | (43) Guest time of the process (time spent running a virtual CPU |
7a017e24 | 1380 | for a guest operating system), measured in clock ticks (divide by |
67914165 | 1381 | .IR sysconf(_SC_CLK_TCK) ). |
14c06953 MK |
1382 | .TP |
1383 | \fIcguest_time\fP %ld (since Linux 2.6.24) | |
aa610245 | 1384 | (44) Guest time of the process's children, measured in clock ticks (divide by |
67914165 | 1385 | .IR sysconf(_SC_CLK_TCK) ). |
fea681da MK |
1386 | .RE |
1387 | .TP | |
69119dc7 | 1388 | .I /proc/[pid]/statm |
59a40ed7 | 1389 | Provides information about memory usage, measured in pages. |
c13182ef | 1390 | The columns are: |
a08ea57c MK |
1391 | .in +4n |
1392 | .nf | |
1393 | ||
cb42fb56 | 1394 | size (1) total program size |
69119dc7 | 1395 | (same as VmSize in \fI/proc/[pid]/status\fP) |
cb42fb56 | 1396 | resident (2) resident set size |
69119dc7 | 1397 | (same as VmRSS in \fI/proc/[pid]/status\fP) |
cb42fb56 MK |
1398 | share (3) shared pages (i.e., backed by a file) |
1399 | text (4) text (code) | |
59a40ed7 | 1400 | .\" (not including libs; broken, includes data segment) |
cb42fb56 MK |
1401 | lib (5) library (unused in Linux 2.6) |
1402 | data (6) data + stack | |
59a40ed7 | 1403 | .\" (including libs; broken, includes library text) |
cb42fb56 | 1404 | dt (7) dirty pages (unused in Linux 2.6) |
a08ea57c MK |
1405 | .fi |
1406 | .in | |
fea681da | 1407 | .TP |
69119dc7 | 1408 | .I /proc/[pid]/status |
fea681da | 1409 | Provides much of the information in |
69119dc7 | 1410 | .I /proc/[pid]/stat |
fea681da | 1411 | and |
69119dc7 | 1412 | .I /proc/[pid]/statm |
fea681da | 1413 | in a format that's easier for humans to parse. |
16b5f7ba MK |
1414 | Here's an example: |
1415 | .in +4n | |
1416 | .nf | |
1417 | ||
b43a3b30 | 1418 | .RB "$" " cat /proc/$$/status" |
16b5f7ba MK |
1419 | Name: bash |
1420 | State: S (sleeping) | |
1421 | Tgid: 3515 | |
1422 | Pid: 3515 | |
1423 | PPid: 3452 | |
1424 | TracerPid: 0 | |
1425 | Uid: 1000 1000 1000 1000 | |
1426 | Gid: 100 100 100 100 | |
1427 | FDSize: 256 | |
1428 | Groups: 16 33 100 | |
1429 | VmPeak: 9136 kB | |
1430 | VmSize: 7896 kB | |
1431 | VmLck: 0 kB | |
1432 | VmHWM: 7572 kB | |
1433 | VmRSS: 6316 kB | |
1434 | VmData: 5224 kB | |
1435 | VmStk: 88 kB | |
1436 | VmExe: 572 kB | |
1437 | VmLib: 1708 kB | |
1438 | VmPTE: 20 kB | |
1439 | Threads: 1 | |
1440 | SigQ: 0/3067 | |
1441 | SigPnd: 0000000000000000 | |
1442 | ShdPnd: 0000000000000000 | |
1443 | SigBlk: 0000000000010000 | |
1444 | SigIgn: 0000000000384004 | |
1445 | SigCgt: 000000004b813efb | |
1446 | CapInh: 0000000000000000 | |
1447 | CapPrm: 0000000000000000 | |
1448 | CapEff: 0000000000000000 | |
1449 | CapBnd: ffffffffffffffff | |
1450 | Cpus_allowed: 00000001 | |
1451 | Cpus_allowed_list: 0 | |
1452 | Mems_allowed: 1 | |
1453 | Mems_allowed_list: 0 | |
1454 | voluntary_ctxt_switches: 150 | |
1455 | nonvoluntary_ctxt_switches: 545 | |
1456 | .fi | |
1457 | .in | |
1458 | .IP | |
1459 | The fields are as follows: | |
1460 | .RS | |
1461 | .IP * 2 | |
1462 | .IR Name : | |
1463 | Command run by this process. | |
1464 | .IP * | |
1465 | .IR State : | |
4175f999 MK |
1466 | Current state of the process. |
1467 | One of | |
16b5f7ba MK |
1468 | "R (running)", |
1469 | "S (sleeping)", | |
1470 | "D (disk sleep)", | |
1471 | "T (stopped)", | |
1472 | "T (tracing stop)", | |
1473 | "Z (zombie)", | |
1474 | or | |
1475 | "X (dead)". | |
1476 | .IP * | |
1477 | .IR Tgid : | |
1478 | Thread group ID (i.e., Process ID). | |
1479 | .IP * | |
1480 | .IR Pid : | |
1481 | Thread ID (see | |
1482 | .BR gettid (2)). | |
1483 | .IP * | |
a1bc91d5 MK |
1484 | .IR PPid : |
1485 | PID of parent process. | |
1486 | .IP * | |
16b5f7ba MK |
1487 | .IR TracerPid : |
1488 | PID of process tracing this process (0 if not being traced). | |
1489 | .IP * | |
1490 | .IR Uid ", " Gid : | |
9ee4a2b6 | 1491 | Real, effective, saved set, and filesystem UIDs (GIDs). |
16b5f7ba MK |
1492 | .IP * |
1493 | .IR FDSize : | |
1494 | Number of file descriptor slots currently allocated. | |
1495 | .IP * | |
1496 | .IR Groups : | |
1497 | Supplementary group list. | |
1498 | .IP * | |
1499 | .IR VmPeak : | |
1500 | Peak virtual memory size. | |
1501 | .IP * | |
1502 | .IR VmSize : | |
1503 | Virtual memory size. | |
1504 | .IP * | |
1505 | .IR VmLck : | |
fde39195 MK |
1506 | Locked memory size (see |
1507 | .BR mlock (3)). | |
16b5f7ba MK |
1508 | .IP * |
1509 | .IR VmHWM : | |
1510 | Peak resident set size ("high water mark"). | |
1511 | .IP * | |
1512 | .IR VmRSS : | |
1513 | Resident set size. | |
1514 | .IP * | |
1515 | .IR VmData ", " VmStk ", " VmExe : | |
1516 | Size of data, stack, and text segments. | |
1517 | .IP * | |
1518 | .IR VmLib : | |
1519 | Shared library code size. | |
1520 | .IP * | |
1521 | .IR VmPTE : | |
1522 | Page table entries size (since Linux 2.6.10). | |
1523 | .IP * | |
1524 | .IR Threads : | |
1525 | Number of threads in process containing this thread. | |
1526 | .IP * | |
6ee625eb MK |
1527 | .IR SigQ : |
1528 | This field contains two slash-separated numbers that relate to | |
1529 | queued signals for the real user ID of this process. | |
1530 | The first of these is the number of currently queued | |
1531 | signals for this real user ID, and the second is the | |
1532 | resource limit on the number of queued signals for this process | |
1533 | (see the description of | |
1534 | .BR RLIMIT_SIGPENDING | |
1535 | in | |
1536 | .BR getrlimit (2)). | |
1537 | .IP * | |
16b5f7ba MK |
1538 | .IR SigPnd ", " ShdPnd : |
1539 | Number of signals pending for thread and for process as a whole (see | |
1540 | .BR pthreads (7) | |
1541 | and | |
1542 | .BR signal (7)). | |
1543 | .IP * | |
1544 | .IR SigBlk ", " SigIgn ", " SigCgt : | |
1545 | Masks indicating signals being blocked, ignored, and caught (see | |
1546 | .BR signal (7)). | |
1547 | .IP * | |
1548 | .IR CapInh ", " CapPrm ", " CapEff : | |
1549 | Masks of capabilities enabled in inheritable, permitted, and effective sets | |
1550 | (see | |
1551 | .BR capabilities (7)). | |
1552 | .IP * | |
1553 | .IR CapBnd : | |
1554 | Capability Bounding set | |
1555 | (since kernel 2.6.26, see | |
1556 | .BR capabilities (7)). | |
1557 | .IP * | |
1558 | .IR Cpus_allowed : | |
1559 | Mask of CPUs on which this process may run | |
1560 | (since Linux 2.6.24, see | |
1561 | .BR cpuset (7)). | |
1562 | .IP * | |
1563 | .IR Cpus_allowed_list : | |
1564 | Same as previous, but in "list format" | |
1565 | (since Linux 2.6.26, see | |
1566 | .BR cpuset (7)). | |
1567 | .IP * | |
1568 | .IR Mems_allowed : | |
1569 | Mask of memory nodes allowed to this process | |
1570 | (since Linux 2.6.24, see | |
1571 | .BR cpuset (7)). | |
1572 | .IP * | |
1573 | .IR Mems_allowed_list : | |
1574 | Same as previous, but in "list format" | |
1575 | (since Linux 2.6.26, see | |
1576 | .BR cpuset (7)). | |
1577 | .IP * | |
1578 | .IR voluntary_context_switches ", " nonvoluntary_context_switches : | |
1579 | Number of voluntary and involuntary context switches (since Linux 2.6.23). | |
1580 | .RE | |
fea681da | 1581 | .TP |
69119dc7 | 1582 | .IR /proc/[pid]/task " (since Linux 2.6.0-test6)" |
afcaf646 MK |
1583 | This is a directory that contains one subdirectory |
1584 | for each thread in the process. | |
69119dc7 MK |
1585 | The name of each subdirectory is the numerical thread ID |
1586 | .RI ( [tid] ) | |
1587 | of the thread (see | |
afcaf646 MK |
1588 | .BR gettid (2)). |
1589 | Within each of these subdirectories, there is a set of | |
1590 | files with the same names and contents as under the | |
69119dc7 | 1591 | .I /proc/[pid] |
afcaf646 MK |
1592 | directories. |
1593 | For attributes that are shared by all threads, the contents for | |
1594 | each of the files under the | |
69119dc7 | 1595 | .I task/[tid] |
afcaf646 | 1596 | subdirectories will be the same as in the corresponding |
c13182ef | 1597 | file in the parent |
69119dc7 | 1598 | .I /proc/[pid] |
afcaf646 | 1599 | directory |
c13182ef | 1600 | (e.g., in a multithreaded process, all of the |
69119dc7 | 1601 | .I task/[tid]/cwd |
c13182ef | 1602 | files will have the same value as the |
69119dc7 | 1603 | .I /proc/[pid]/cwd |
c13182ef | 1604 | file in the parent directory, since all of the threads in a process |
afcaf646 MK |
1605 | share a working directory). |
1606 | For attributes that are distinct for each thread, | |
c13182ef | 1607 | the corresponding files under |
69119dc7 | 1608 | .I task/[tid] |
afcaf646 | 1609 | may have different values (e.g., various fields in each of the |
69119dc7 | 1610 | .I task/[tid]/status |
afcaf646 MK |
1611 | files may be different for each thread). |
1612 | ||
1613 | .\" The following was still true as at kernel 2.6.13 | |
1614 | In a multithreaded process, the contents of the | |
69119dc7 | 1615 | .I /proc/[pid]/task |
c13182ef | 1616 | directory are not available if the main thread has already terminated |
afcaf646 MK |
1617 | (typically by calling |
1618 | .BR pthread_exit (3)). | |
1619 | .TP | |
2054f761 MK |
1620 | .IR /proc/[pid]/wchan " (since Linux 2.6.0)" |
1621 | The symbolic name corresponding to the location | |
1622 | in the kernel where the process is sleeping. | |
1623 | .TP | |
fea681da | 1624 | .I /proc/apm |
097585ed MK |
1625 | Advanced power management version and battery information when |
1626 | .B CONFIG_APM | |
1627 | is defined at kernel compilation time. | |
fea681da MK |
1628 | .TP |
1629 | .I /proc/bus | |
1630 | Contains subdirectories for installed busses. | |
1631 | .TP | |
1632 | .I /proc/bus/pccard | |
59a40ed7 | 1633 | Subdirectory for PCMCIA devices when |
097585ed MK |
1634 | .B CONFIG_PCMCIA |
1635 | is set at kernel compilation time. | |
fea681da | 1636 | .TP |
1509ca0e MK |
1637 | .IR /proc/[pid]/timers " (since Linux 3.10)" |
1638 | .\" commit 5ed67f05f66c41e39880a6d61358438a25f9fee5 | |
1639 | .\" commit 48f6a7a511ef8823fdff39afee0320092d43a8a0 | |
1640 | A list of the POSIX timers for this process. | |
9d54c087 | 1641 | Each timer is listed with a line that started with the string "ID:". |
1509ca0e MK |
1642 | For example: |
1643 | ||
1644 | .in +4n | |
1645 | .nf | |
1646 | ID: 1 | |
1647 | signal: 60/00007fff86e452a8 | |
1648 | notify: signal/pid.2634 | |
1649 | ClockID: 0 | |
1650 | ID: 0 | |
1651 | signal: 60/00007fff86e452a8 | |
1652 | notify: signal/pid.2634 | |
1653 | ClockID: 1 | |
1654 | .fi | |
1655 | .in | |
1656 | ||
1657 | The lines shown for each timer have the following meanings: | |
1658 | .RS | |
1659 | .TP | |
1660 | .I ID | |
1661 | The ID for this timer. | |
1662 | This is not the same as the timer ID returned by | |
1663 | .BR timer_create (2); | |
1664 | rather, it is the same kernel-internal ID that is available via the | |
1665 | .I si_timerid | |
1666 | field of the | |
1667 | .IR siginfo_t | |
1668 | structure (see | |
1669 | .BR sigaction (2)). | |
1670 | .TP | |
1671 | .I signal | |
1672 | This is the signal number that this timer uses to deliver notifications | |
1673 | followed by a slash, and then the | |
1674 | .I sigev_value.sival_ptr | |
1675 | value supplied to the signal handler. | |
1676 | Valid only for timers that notify via a signal. | |
1677 | .TP | |
1678 | .I notify | |
1679 | The part before the slash specifies the mechanism | |
1680 | that this timer uses to deliver notifications, | |
1681 | and is one of "thread", "signal", or "none". | |
1682 | Immediately following the slash is either the string "tid" for timers | |
1683 | with | |
1684 | .B SIGEV_THREAD_ID | |
1685 | notification, or "pid" for timers that notify by other mechanisms. | |
1686 | Following the "." is the PID of the process that will be delivered | |
1687 | a signal if the timer delivers notifications via a signal. | |
1688 | .TP | |
1689 | .I ClockID | |
1690 | This field identifies the clock that the timer uses for measuring time. | |
1691 | For most clocks, this is a number that matches one of the user-space | |
1692 | .BR CLOCK_* | |
9d54c087 | 1693 | constants exposed via |
1509ca0e MK |
1694 | .IR <time.h> . |
1695 | .B CLOCK_PROCESS_CPUTIME_ID | |
1696 | timers display with a value of -6 | |
1697 | in this field. | |
1698 | .B CLOCK_THREAD_CPUTIME_ID | |
1699 | timers display with a value of -2 | |
1700 | in this field. | |
1701 | .RE | |
1702 | .TP | |
fea681da MK |
1703 | .I /proc/bus/pccard/drivers |
1704 | .TP | |
1705 | .I /proc/bus/pci | |
c13182ef | 1706 | Contains various bus subdirectories and pseudo-files containing |
59a40ed7 | 1707 | information about PCI busses, installed devices, and device |
c13182ef MK |
1708 | drivers. |
1709 | Some of these files are not ASCII. | |
fea681da MK |
1710 | .TP |
1711 | .I /proc/bus/pci/devices | |
59a40ed7 | 1712 | Information about PCI devices. |
c13182ef | 1713 | They may be accessed through |
fea681da MK |
1714 | .BR lspci (8) |
1715 | and | |
1716 | .BR setpci (8). | |
1717 | .TP | |
1718 | .I /proc/cmdline | |
c13182ef MK |
1719 | Arguments passed to the Linux kernel at boot time. |
1720 | Often done via a boot manager such as | |
59a40ed7 MK |
1721 | .BR lilo (8) |
1722 | or | |
1723 | .BR grub (8). | |
f6e524c4 MK |
1724 | .TP |
1725 | .IR /proc/config.gz " (since Linux 2.6)" | |
1726 | This file exposes the configuration options that were used | |
c3d9780d | 1727 | to build the currently running kernel, |
f6e524c4 MK |
1728 | in the same format as they would be shown in the |
1729 | .I .config | |
1730 | file that resulted when configuring the kernel (using | |
1731 | .IR "make xconfig" , | |
1732 | .IR "make config" , | |
1733 | or similar). | |
1734 | The file contents are compressed; view or search them using | |
f78ed33a MK |
1735 | .BR zcat (1) |
1736 | and | |
1737 | .BR zgrep (1). | |
f6e524c4 | 1738 | As long as no changes have been made to the following file, |
250e01ec MK |
1739 | the contents of |
1740 | .I /proc/config.gz | |
1741 | are the same as those provided by : | |
f6e524c4 MK |
1742 | .in +4n |
1743 | .nf | |
1744 | ||
c3074d70 | 1745 | cat /lib/modules/$(uname \-r)/build/.config |
f6e524c4 MK |
1746 | .fi |
1747 | .in | |
250e01ec MK |
1748 | .IP |
1749 | .I /proc/config.gz | |
90878f7c | 1750 | is provided only if the kernel is configured with |
250e01ec | 1751 | .BR CONFIG_IKCONFIG_PROC . |
fea681da MK |
1752 | .TP |
1753 | .I /proc/cpuinfo | |
1754 | This is a collection of CPU and system architecture dependent items, | |
1755 | for each supported architecture a different list. | |
1756 | Two common entries are \fIprocessor\fP which gives CPU number and | |
c13182ef MK |
1757 | \fIbogomips\fP; a system constant that is calculated |
1758 | during kernel initialization. | |
1759 | SMP machines have information for | |
fea681da | 1760 | each CPU. |
a091f002 MK |
1761 | The |
1762 | .BR lscpu (1) | |
1763 | command gathers its information from this file. | |
fea681da MK |
1764 | .TP |
1765 | .I /proc/devices | |
c13182ef MK |
1766 | Text listing of major numbers and device groups. |
1767 | This can be used by MAKEDEV scripts for consistency with the kernel. | |
fea681da MK |
1768 | .TP |
1769 | .IR /proc/diskstats " (since Linux 2.5.69)" | |
1770 | This file contains disk I/O statistics for each disk device. | |
66a9882e | 1771 | See the Linux kernel source file |
fea681da MK |
1772 | .I Documentation/iostats.txt |
1773 | for further information. | |
1774 | .TP | |
1775 | .I /proc/dma | |
c13182ef | 1776 | This is a list of the registered \fIISA\fP DMA (direct memory access) |
fea681da MK |
1777 | channels in use. |
1778 | .TP | |
1779 | .I /proc/driver | |
1780 | Empty subdirectory. | |
1781 | .TP | |
1782 | .I /proc/execdomains | |
1783 | List of the execution domains (ABI personalities). | |
1784 | .TP | |
1785 | .I /proc/fb | |
097585ed MK |
1786 | Frame buffer information when |
1787 | .B CONFIG_FB | |
1788 | is defined during kernel compilation. | |
fea681da MK |
1789 | .TP |
1790 | .I /proc/filesystems | |
9ee4a2b6 MK |
1791 | A text listing of the filesystems which are supported by the kernel, |
1792 | namely filesystems which were compiled into the kernel or whose kernel | |
6387216b MK |
1793 | modules are currently loaded. |
1794 | (See also | |
fb477da2 | 1795 | .BR filesystems (5).) |
9ee4a2b6 | 1796 | If a filesystem is marked with "nodev", |
809d0164 | 1797 | this means that it does not require a block device to be mounted |
9ee4a2b6 | 1798 | (e.g., virtual filesystem, network filesystem). |
809d0164 MK |
1799 | |
1800 | Incidentally, this file may be used by | |
1801 | .BR mount (8) | |
9ee4a2b6 MK |
1802 | when no filesystem is specified and it didn't manage to determine the |
1803 | filesystem type. | |
1804 | Then filesystems contained in this file are tried | |
809d0164 | 1805 | (excepted those that are marked with "nodev"). |
fea681da MK |
1806 | .TP |
1807 | .I /proc/fs | |
df352acc | 1808 | .\" FIXME Much more needs to be said about /proc/fs |
91085d85 | 1809 | .\" |
df352acc MK |
1810 | Contains subdirectories that in turn contain files |
1811 | with information about (certain) mounted filesystems. | |
fea681da MK |
1812 | .TP |
1813 | .I /proc/ide | |
1814 | This directory | |
59a40ed7 MK |
1815 | exists on systems with the IDE bus. |
1816 | There are directories for each IDE channel and attached device. | |
c13182ef | 1817 | Files include: |
fea681da | 1818 | |
a08ea57c | 1819 | .in +4n |
fea681da MK |
1820 | .nf |
1821 | cache buffer size in KB | |
1822 | capacity number of sectors | |
1823 | driver driver version | |
1824 | geometry physical and logical geometry | |
9fdfa163 | 1825 | identify in hexadecimal |
fea681da MK |
1826 | media media type |
1827 | model manufacturer's model number | |
1828 | settings drive settings | |
9fdfa163 MK |
1829 | smart_thresholds in hexadecimal |
1830 | smart_values in hexadecimal | |
fea681da | 1831 | .fi |
a08ea57c | 1832 | .in |
fea681da | 1833 | |
c13182ef | 1834 | The |
fea681da MK |
1835 | .BR hdparm (8) |
1836 | utility provides access to this information in a friendly format. | |
1837 | .TP | |
1838 | .I /proc/interrupts | |
23ec6ff0 MK |
1839 | This is used to record the number of interrupts per CPU per IO device. |
1840 | Since Linux 2.6.24, | |
1841 | for the i386 and x86_64 architectures, at least, this also includes | |
1842 | interrupts internal to the system (that is, not associated with a device | |
1843 | as such), such as NMI (nonmaskable interrupt), LOC (local timer interrupt), | |
1844 | and for SMP systems, TLB (TLB flush interrupt), RES (rescheduling | |
1845 | interrupt), CAL (remote function call interrupt), and possibly others. | |
1846 | Very easy to read formatting, done in ASCII. | |
fea681da MK |
1847 | .TP |
1848 | .I /proc/iomem | |
1849 | I/O memory map in Linux 2.4. | |
1850 | .TP | |
1851 | .I /proc/ioports | |
c13182ef | 1852 | This is a list of currently registered Input-Output port regions that |
fea681da MK |
1853 | are in use. |
1854 | .TP | |
1855 | .IR /proc/kallsyms " (since Linux 2.5.71)" | |
1856 | This holds the kernel exported symbol definitions used by the | |
1857 | .BR modules (X) | |
1858 | tools to dynamically link and bind loadable modules. | |
1859 | In Linux 2.5.47 and earlier, a similar file with slightly different syntax | |
1860 | was named | |
1861 | .IR ksyms . | |
1862 | .TP | |
1863 | .I /proc/kcore | |
1864 | This file represents the physical memory of the system and is stored | |
c13182ef MK |
1865 | in the ELF core file format. |
1866 | With this pseudo-file, and an unstripped | |
9a67332e MK |
1867 | kernel |
1868 | .RI ( /usr/src/linux/vmlinux ) | |
1869 | binary, GDB can be used to | |
fea681da MK |
1870 | examine the current state of any kernel data structures. |
1871 | ||
1872 | The total length of the file is the size of physical memory (RAM) plus | |
1873 | 4KB. | |
1874 | .TP | |
1875 | .I /proc/kmsg | |
1876 | This file can be used instead of the | |
1877 | .BR syslog (2) | |
c13182ef MK |
1878 | system call to read kernel messages. |
1879 | A process must have superuser | |
fea681da | 1880 | privileges to read this file, and only one process should read this |
c13182ef MK |
1881 | file. |
1882 | This file should not be read if a syslog process is running | |
fea681da MK |
1883 | which uses the |
1884 | .BR syslog (2) | |
1885 | system call facility to log kernel messages. | |
1886 | ||
1887 | Information in this file is retrieved with the | |
c4517613 | 1888 | .BR dmesg (1) |
fea681da MK |
1889 | program. |
1890 | .TP | |
1891 | .IR /proc/ksyms " (Linux 1.1.23-2.5.47)" | |
1892 | See | |
1893 | .IR /proc/kallsyms . | |
1894 | .TP | |
1895 | .I /proc/loadavg | |
6b05dc38 MK |
1896 | The first three fields in this file are load average figures |
1897 | giving the number of jobs in the run queue (state R) | |
fea681da MK |
1898 | or waiting for disk I/O (state D) averaged over 1, 5, and 15 minutes. |
1899 | They are the same as the load average numbers given by | |
1900 | .BR uptime (1) | |
1901 | and other programs. | |
6b05dc38 | 1902 | The fourth field consists of two numbers separated by a slash (/). |
78fc91ec EDB |
1903 | The first of these is the number of currently runnable kernel |
1904 | scheduling entities (processes, threads). | |
6b05dc38 MK |
1905 | The value after the slash is the number of kernel scheduling entities |
1906 | that currently exist on the system. | |
1907 | The fifth field is the PID of the process that was most | |
1908 | recently created on the system. | |
fea681da MK |
1909 | .TP |
1910 | .I /proc/locks | |
1911 | This file shows current file locks | |
1912 | .RB ( flock "(2) and " fcntl (2)) | |
1913 | and leases | |
1914 | .RB ( fcntl (2)). | |
1915 | .TP | |
89dd5f8a | 1916 | .IR /proc/malloc " (only up to and including Linux 2.2)" |
59a40ed7 | 1917 | .\" It looks like this only ever did something back in 1.0 days |
90878f7c | 1918 | This file is present only if |
89dd5f8a | 1919 | .B CONFIG_DEBUG_MALLOC |
097585ed | 1920 | was defined during compilation. |
fea681da MK |
1921 | .TP |
1922 | .I /proc/meminfo | |
77b802ec MK |
1923 | This file reports statistics about memory usage on the system. |
1924 | It is used by | |
fea681da MK |
1925 | .BR free (1) |
1926 | to report the amount of free and used memory (both physical and swap) | |
1927 | on the system as well as the shared memory and buffers used by the | |
1928 | kernel. | |
3ba3d5b1 MK |
1929 | Each line of the file consists of a parameter name, followed by a colon, |
1930 | the value of the parameter, and an option unit of measurement (e.g., "kB"). | |
1931 | The list below describes the parameter names and | |
1932 | the format specifier required to read the field value. | |
1933 | Except as noted below, | |
1934 | all of the fields have been present since at least Linux 2.6.0. | |
86cf87d7 | 1935 | Some fields are displayed only if the kernel was configured |
3ba3d5b1 MK |
1936 | with various options; those dependencies are noted in the list. |
1937 | .RS | |
1938 | .TP | |
1939 | .IR MemTotal " %lu" | |
449dd4e2 | 1940 | Total usable RAM (i.e., physical RAM minus a few reserved |
99e91586 | 1941 | bits and the kernel binary code). |
3ba3d5b1 MK |
1942 | .TP |
1943 | .IR MemFree " %lu" | |
7bccb7d4 DP |
1944 | The sum of |
1945 | .IR LowFree + HighFree . | |
3ba3d5b1 MK |
1946 | .TP |
1947 | .IR Buffers " %lu" | |
99e91586 | 1948 | Relatively temporary storage for raw disk blocks that |
3ba3d5b1 MK |
1949 | shouldn't get tremendously large (20MB or so). |
1950 | .TP | |
1951 | .IR Cached " %lu" | |
1952 | In-memory cache for files read from the disk (the page cache). | |
1953 | Doesn't include | |
1954 | .IR SwapCached . | |
1955 | .TP | |
1956 | .IR SwapCached " %lu" | |
1957 | Memory that once was swapped out, is swapped back in but | |
1958 | still also is in the swap file. | |
fa1d2749 | 1959 | (If memory pressure is high, these pages |
3ba3d5b1 | 1960 | don't need to be swapped out again because they are already |
99e91586 | 1961 | in the swap file. |
3ba3d5b1 MK |
1962 | This saves I/O.) |
1963 | .TP | |
1964 | .IR Active " %lu" | |
1965 | Memory that has been used more recently and usually not | |
1966 | reclaimed unless absolutely necessary. | |
1967 | .TP | |
1968 | .IR Inactive " %lu" | |
1969 | Memory which has been less recently used. | |
1970 | It is more eligible to be reclaimed for other purposes. | |
1971 | .TP | |
1972 | .IR Active(anon) " %lu (since Linux 2.6.28)" | |
1973 | [To be documented.] | |
1974 | .TP | |
1975 | .IR Inactive(anon) " %lu (since Linux 2.6.28)" | |
1976 | [To be documented.] | |
1977 | .TP | |
1978 | .IR Active(file) " %lu (since Linux 2.6.28)" | |
1979 | [To be documented.] | |
1980 | .TP | |
1981 | .IR Inactive(file) " %lu (since Linux 2.6.28)" | |
1982 | [To be documented.] | |
1983 | .TP | |
1984 | .IR Unevictable " %lu (since Linux 2.6.28)" | |
1985 | (From Linux 2.6.28 to 2.6.30, | |
1986 | \fBCONFIG_UNEVICTABLE_LRU\fP was required.) | |
1987 | [To be documented.] | |
1988 | .TP | |
46fbfc07 | 1989 | .IR Mlocked " %lu (since Linux 2.6.28)" |
3ba3d5b1 MK |
1990 | (From Linux 2.6.28 to 2.6.30, |
1991 | \fBCONFIG_UNEVICTABLE_LRU\fP was required.) | |
1992 | [To be documented.] | |
1993 | .TP | |
1994 | .IR HighTotal " %lu" | |
1995 | (Starting with Linux 2.6.19, \fBCONFIG_HIGHMEM\fP is required.) | |
1996 | Total amount of highmem. | |
99e91586 | 1997 | Highmem is all memory above ~860MB of physical memory. |
3ba3d5b1 MK |
1998 | Highmem areas are for use by user-space programs, |
1999 | or for the page cache. | |
2000 | The kernel must use tricks to access | |
2001 | this memory, making it slower to access than lowmem. | |
2002 | .TP | |
2003 | .IR HighFree " %lu | |
2004 | (Starting with Linux 2.6.19, \fBCONFIG_HIGHMEM\fP is required.) | |
2005 | Amount of free highmem. | |
2006 | .TP | |
2007 | .IR LowTotal " %lu | |
2008 | (Starting with Linux 2.6.19, \fBCONFIG_HIGHMEM\fP is required.) | |
2009 | Total amount of lowmem. | |
2010 | Lowmem is memory which can be used for everything that | |
2011 | highmem can be used for, but it is also available for the | |
2012 | kernel's use for its own data structures. | |
2013 | Among many other things, | |
99e91586 | 2014 | it is where everything from |
7bccb7d4 DP |
2015 | .I Slab |
2016 | is allocated. | |
3ba3d5b1 MK |
2017 | Bad things happen when you're out of lowmem. |
2018 | .TP | |
2019 | .IR LowFree " %lu | |
2020 | (Starting with Linux 2.6.19, \fBCONFIG_HIGHMEM\fP is required.) | |
2021 | Amount of free lowmem. | |
2022 | .TP | |
2023 | .IR MmapCopy " %lu (since Linux 2.6.29)" | |
99e91586 DP |
2024 | .RB ( CONFIG_MMU |
2025 | is required.) | |
3ba3d5b1 MK |
2026 | [To be documented.] |
2027 | .TP | |
2028 | .IR SwapTotal " %lu" | |
2029 | Total amount of swap space available. | |
2030 | .TP | |
2031 | .IR SwapFree " %lu" | |
c16d4f25 | 2032 | Amount of swap space that is currently unused. |
3ba3d5b1 MK |
2033 | .TP |
2034 | .IR Dirty " %lu" | |
2035 | Memory which is waiting to get written back to the disk. | |
2036 | .TP | |
2037 | .IR Writeback " %lu" | |
2038 | Memory which is actively being written back to the disk. | |
2039 | .TP | |
2040 | .IR AnonPages " %lu (since Linux 2.6.18)" | |
2041 | Non-file backed pages mapped into user-space page tables. | |
2042 | .TP | |
2043 | .IR Mapped " %lu" | |
fda70f5b MK |
2044 | Files which have been mapped into memory (with |
2045 | .BR mmap (2)), | |
2046 | such as libraries. | |
3ba3d5b1 MK |
2047 | .TP |
2048 | .IR Shmem " %lu (since Linux 2.6.32)" | |
2049 | [To be documented.] | |
2050 | .TP | |
2051 | .IR Slab " %lu" | |
2052 | In-kernel data structures cache. | |
2053 | .TP | |
2054 | .IR SReclaimable " %lu (since Linux 2.6.19)" | |
7bccb7d4 DP |
2055 | Part of |
2056 | .IR Slab , | |
2057 | that might be reclaimed, such as caches. | |
3ba3d5b1 MK |
2058 | .TP |
2059 | .IR SUnreclaim " %lu (since Linux 2.6.19)" | |
7bccb7d4 DP |
2060 | Part of |
2061 | .IR Slab , | |
2062 | that cannot be reclaimed on memory pressure. | |
3ba3d5b1 MK |
2063 | .TP |
2064 | .IR KernelStack " %lu (since Linux 2.6.32)" | |
2065 | Amount of memory allocated to kernel stacks. | |
2066 | .TP | |
2067 | .IR PageTables " %lu (since Linux 2.6.18)" | |
2068 | Amount of memory dedicated to the lowest level of page tables. | |
2069 | .TP | |
2070 | .IR Quicklists " %lu (since Linux 2.6.27)" | |
2071 | (\fBCONFIG_QUICKLIST\fP is required.) | |
2072 | [To be documented.] | |
2073 | .TP | |
2074 | .IR NFS_Unstable " %lu (since Linux 2.6.18)" | |
2075 | NFS pages sent to the server, but not yet committed to stable storage. | |
2076 | .TP | |
2077 | .IR Bounce " %lu (since Linux 2.6.18)" | |
2078 | Memory used for block device "bounce buffers". | |
2079 | .TP | |
2080 | .IR WritebackTmp " %lu (since Linux 2.6.26)" | |
2081 | Memory used by FUSE for temporary writeback buffers. | |
2082 | .TP | |
2083 | .IR CommitLimit " %lu (since Linux 2.6.10)" | |
2084 | Based on the overcommit ratio ('vm.overcommit_ratio'), | |
d6a56978 | 2085 | this is the total amount of memory currently available to |
90878f7c MK |
2086 | be allocated on the system. |
2087 | This limit is adhered to | |
2088 | only if strict overcommit accounting is enabled (mode 2 in | |
3ba3d5b1 MK |
2089 | .IR /proc/sys/vm/overcommit_ratio ). |
2090 | The | |
2091 | .I CommitLimit | |
2092 | is calculated using the following formula: | |
2093 | ||
d102a673 | 2094 | CommitLimit = |
d3532647 | 2095 | ([total RAM pages] - [total huge TLB pages]) * |
d102a673 | 2096 | overcommit_ratio / 100 + [total swap pages] |
3ba3d5b1 MK |
2097 | |
2098 | For example, on a system with 1GB of physical RAM and 7GB | |
2099 | of swap with a | |
2100 | .I overcommit_ratio | |
2101 | of 30, this formula yields a | |
2102 | .I CommitLimit | |
99e91586 | 2103 | of 7.3GB. |
3ba3d5b1 | 2104 | For more details, see the memory overcommit documentation |
99e91586 | 2105 | in the kernel source file |
3ba3d5b1 MK |
2106 | .IR Documentation/vm/overcommit-accounting . |
2107 | .TP | |
2108 | .IR Committed_AS " %lu" | |
2109 | The amount of memory presently allocated on the system. | |
2110 | The committed memory is a sum of all of the memory which | |
2111 | has been allocated by processes, even if it has not been | |
2112 | "used" by them as of yet. | |
2113 | A process which allocates 1GB of memory (using | |
2114 | .BR malloc (3) | |
33a0ccb2 | 2115 | or similar), but touches only 300MB of that memory will show up |
90878f7c | 2116 | as using only 300MB of memory even if it has the address space |
3ba3d5b1 MK |
2117 | allocated for the entire 1GB. |
2118 | This 1GB is memory which has been "committed" to by the VM | |
2119 | and can be used at any time by the allocating application. | |
2120 | With strict overcommit enabled on the system (mode 2 | |
99e91586 | 2121 | .IR /proc/sys/vm/overcommit_memory ), |
3ba3d5b1 MK |
2122 | allocations which would exceed the |
2123 | .I CommitLimit | |
2124 | (detailed above) will not be permitted. | |
2125 | This is useful if one needs to guarantee that processes will not | |
2126 | fail due to lack of memory once that memory has been successfully allocated. | |
2127 | .TP | |
2128 | .IR VmallocTotal " %lu" | |
2129 | Total size of vmalloc memory area. | |
2130 | .TP | |
2131 | .IR VmallocUsed " %lu" | |
2132 | Amount of vmalloc area which is used. | |
2133 | .TP | |
2134 | .IR VmallocChunk " %lu" | |
2135 | Largest contiguous block of vmalloc area which is free. | |
2136 | .TP | |
2137 | .IR HardwareCorrupted " %lu (since Linux 2.6.32)" | |
2138 | (\fBCONFIG_MEMORY_FAILURE\fP is required.) | |
2139 | [To be documented.] | |
2140 | .TP | |
2141 | .IR AnonHugePages " %lu (since Linux 2.6.38)" | |
2142 | (\fBCONFIG_TRANSPARENT_HUGEPAGE\fP is required.) | |
7fac88a9 | 2143 | Non-file backed huge pages mapped into user-space page tables. |
3ba3d5b1 MK |
2144 | .TP |
2145 | .IR HugePages_Total " %lu" | |
2146 | (\fBCONFIG_HUGETLB_PAGE\fP is required.) | |
2147 | The size of the pool of huge pages. | |
2148 | .TP | |
2149 | .IR HugePages_Free " %lu" | |
2150 | (\fBCONFIG_HUGETLB_PAGE\fP is required.) | |
2151 | The number of huge pages in the pool that are not yet allocated. | |
2152 | .TP | |
2153 | .IR HugePages_Rsvd " %lu (since Linux 2.6.17)" | |
2154 | (\fBCONFIG_HUGETLB_PAGE\fP is required.) | |
2155 | This is the number of huge pages for | |
2156 | which a commitment to allocate from the pool has been made, | |
2157 | but no allocation has yet been made. | |
2158 | These reserved huge pages | |
2159 | guarantee that an application will be able to allocate a | |
2160 | huge page from the pool of huge pages at fault time. | |
2161 | .TP | |
aa8a6b4f | 2162 | .IR HugePages_Surp " %lu (since Linux 2.6.24)" |
3ba3d5b1 MK |
2163 | (\fBCONFIG_HUGETLB_PAGE\fP is required.) |
2164 | This is the number of huge pages in | |
2165 | the pool above the value in | |
2166 | .IR /proc/sys/vm/nr_hugepages . | |
2167 | The maximum number of surplus huge pages is controlled by | |
2168 | .IR /proc/sys/vm/nr_overcommit_hugepages . | |
2169 | .TP | |
2170 | .IR Hugepagesize " %lu" | |
2171 | (\fBCONFIG_HUGETLB_PAGE\fP is required.) | |
2172 | The size of huge pages. | |
2173 | .RE | |
fea681da | 2174 | .TP |
aa341984 MK |
2175 | .I /proc/modules |
2176 | A text list of the modules that have been loaded by the system. | |
2177 | See also | |
2178 | .BR lsmod (8). | |
2179 | .TP | |
fea681da | 2180 | .I /proc/mounts |
c1eea65a | 2181 | Before kernel 2.4.19, this file was a list |
9ee4a2b6 | 2182 | of all the filesystems currently mounted on the system. |
732e54dd | 2183 | With the introduction of per-process mount namespaces in |
c1eea65a MK |
2184 | Linux 2.4.19, this file became a link to |
2185 | .IR /proc/self/mounts , | |
732e54dd | 2186 | which lists the mount points of the process's own mount namespace. |
fea681da | 2187 | The format of this file is documented in |
31e9a9ec | 2188 | .BR fstab (5). |
fea681da | 2189 | .TP |
fea681da | 2190 | .I /proc/mtrr |
c13182ef | 2191 | Memory Type Range Registers. |
66a9882e | 2192 | See the Linux kernel source file |
cfe70b66 | 2193 | .I Documentation/mtrr.txt |
fea681da MK |
2194 | for details. |
2195 | .TP | |
2196 | .I /proc/net | |
2197 | various net pseudo-files, all of which give the status of some part of | |
c13182ef MK |
2198 | the networking layer. |
2199 | These files contain ASCII structures and are, | |
59a40ed7 MK |
2200 | therefore, readable with |
2201 | .BR cat (1). | |
c13182ef | 2202 | However, the standard |
fea681da MK |
2203 | .BR netstat (8) |
2204 | suite provides much cleaner access to these files. | |
2205 | .TP | |
2206 | .I /proc/net/arp | |
2207 | This holds an ASCII readable dump of the kernel ARP table used for | |
c13182ef | 2208 | address resolutions. |
01d0a447 | 2209 | It will show both dynamically learned and preprogrammed ARP entries. |
c13182ef | 2210 | The format is: |
fea681da MK |
2211 | |
2212 | .nf | |
2213 | .ft CW | |
2214 | .in 8n | |
2215 | IP address HW type Flags HW address Mask Device | |
2216 | 192.168.0.50 0x1 0x2 00:50:BF:25:68:F3 * eth0 | |
2217 | 192.168.0.250 0x1 0xc 00:00:00:00:00:00 * eth0 | |
2218 | .ft | |
2219 | .fi | |
2220 | .in | |
2221 | ||
6c04f928 | 2222 | Here "IP address" is the IPv4 address of the machine and the "HW type" |
c13182ef MK |
2223 | is the hardware type of the address from RFC\ 826. |
2224 | The flags are the internal | |
9a67332e MK |
2225 | flags of the ARP structure (as defined in |
2226 | .IR /usr/include/linux/if_arp.h ) | |
2227 | and | |
6c04f928 | 2228 | the "HW address" is the data link layer mapping for that IP address if |
fea681da MK |
2229 | it is known. |
2230 | .TP | |
2231 | .I /proc/net/dev | |
c13182ef MK |
2232 | The dev pseudo-file contains network device status information. |
2233 | This gives | |
2234 | the number of received and sent packets, the number of errors and | |
fea681da | 2235 | collisions |
c13182ef MK |
2236 | and other basic statistics. |
2237 | These are used by the | |
fea681da | 2238 | .BR ifconfig (8) |
c13182ef MK |
2239 | program to report device status. |
2240 | The format is: | |
fea681da MK |
2241 | |
2242 | .nf | |
2243 | .ft CW | |
2244 | .in 1n | |
2245 | Inter-| Receive | Transmit | |
2246 | face |bytes packets errs drop fifo frame compressed multicast|bytes packets errs drop fifo colls carrier compressed | |
2247 | lo: 2776770 11307 0 0 0 0 0 0 2776770 11307 0 0 0 0 0 0 | |
2248 | eth0: 1215645 2751 0 0 0 0 0 0 1782404 4324 0 0 0 427 0 0 | |
2249 | ppp0: 1622270 5552 1 0 0 0 0 0 354130 5669 0 0 0 0 0 0 | |
2250 | tap0: 7714 81 0 0 0 0 0 0 7714 81 0 0 0 0 0 0 | |
2251 | .in | |
2252 | .ft | |
2253 | .fi | |
2254 | .\" .TP | |
2255 | .\" .I /proc/net/ipx | |
2256 | .\" No information. | |
2257 | .\" .TP | |
2258 | .\" .I /proc/net/ipx_route | |
2259 | .\" No information. | |
2260 | .TP | |
2261 | .I /proc/net/dev_mcast | |
2262 | Defined in | |
2263 | .IR /usr/src/linux/net/core/dev_mcast.c : | |
2264 | .nf | |
2265 | .in +5 | |
9fdfa163 | 2266 | indx interface_name dmi_u dmi_g dmi_address |
fea681da MK |
2267 | 2 eth0 1 0 01005e000001 |
2268 | 3 eth1 1 0 01005e000001 | |
2269 | 4 eth2 1 0 01005e000001 | |
2270 | .in | |
2271 | .fi | |
2272 | .TP | |
2273 | .I /proc/net/igmp | |
c13182ef MK |
2274 | Internet Group Management Protocol. |
2275 | Defined in | |
fea681da MK |
2276 | .IR /usr/src/linux/net/core/igmp.c . |
2277 | .TP | |
2278 | .I /proc/net/rarp | |
2279 | This file uses the same format as the | |
2280 | .I arp | |
2281 | file and contains the current reverse mapping database used to provide | |
2282 | .BR rarp (8) | |
c13182ef MK |
2283 | reverse address lookup services. |
2284 | If RARP is not configured into the | |
fea681da MK |
2285 | kernel, |
2286 | this file will not be present. | |
2287 | .TP | |
2288 | .I /proc/net/raw | |
c13182ef MK |
2289 | Holds a dump of the RAW socket table. |
2290 | Much of the information is not of | |
fea681da | 2291 | use |
c13182ef | 2292 | apart from debugging. |
6c04f928 | 2293 | The "sl" value is the kernel hash slot for the |
fea681da | 2294 | socket, |
6c04f928 MK |
2295 | the "local_address" is the local address and protocol number pair. |
2296 | \&"St" is | |
c13182ef MK |
2297 | the internal status of the socket. |
2298 | The "tx_queue" and "rx_queue" are the | |
fea681da | 2299 | outgoing and incoming data queue in terms of kernel memory usage. |
94e9d9fe | 2300 | The "tr", "tm\->when", and "rexmits" fields are not used by RAW. |
fdc196f5 MK |
2301 | The "uid" |
2302 | field holds the effective UID of the creator of the socket. | |
fea681da MK |
2303 | .\" .TP |
2304 | .\" .I /proc/net/route | |
2305 | .\" No information, but looks similar to | |
2306 | .\" .BR route (8). | |
2307 | .TP | |
2308 | .I /proc/net/snmp | |
c13182ef | 2309 | This file holds the ASCII data needed for the IP, ICMP, TCP, and UDP |
fea681da | 2310 | management |
763f0e47 | 2311 | information bases for an SNMP agent. |
fea681da MK |
2312 | .TP |
2313 | .I /proc/net/tcp | |
c13182ef MK |
2314 | Holds a dump of the TCP socket table. |
2315 | Much of the information is not | |
2316 | of use apart from debugging. | |
2317 | The "sl" value is the kernel hash slot | |
6beb1671 MK |
2318 | for the socket, the "local_address" is the local address and port number pair. |
2319 | The "rem_address" is the remote address and port number pair | |
6c04f928 MK |
2320 | (if connected). |
2321 | \&"St" is the internal status of the socket. | |
2322 | The "tx_queue" and "rx_queue" are the | |
fea681da | 2323 | outgoing and incoming data queue in terms of kernel memory usage. |
94e9d9fe | 2324 | The "tr", "tm\->when", and "rexmits" fields hold internal information of |
fdc196f5 MK |
2325 | the kernel socket state and are only useful for debugging. |
2326 | The "uid" | |
2327 | field holds the effective UID of the creator of the socket. | |
fea681da MK |
2328 | .TP |
2329 | .I /proc/net/udp | |
c13182ef MK |
2330 | Holds a dump of the UDP socket table. |
2331 | Much of the information is not of | |
2332 | use apart from debugging. | |
2333 | The "sl" value is the kernel hash slot for the | |
6beb1671 MK |
2334 | socket, the "local_address" is the local address and port number pair. |
2335 | The "rem_address" is the remote address and port number pair | |
fea681da MK |
2336 | (if connected). "St" is the internal status of the socket. |
2337 | The "tx_queue" and "rx_queue" are the outgoing and incoming data queue | |
c13182ef | 2338 | in terms of kernel memory usage. |
94e9d9fe | 2339 | The "tr", "tm\->when", and "rexmits" fields |
c13182ef | 2340 | are not used by UDP. |
fdc196f5 MK |
2341 | The "uid" |
2342 | field holds the effective UID of the creator of the socket. | |
fea681da MK |
2343 | The format is: |
2344 | ||
2345 | .nf | |
2346 | .ft CW | |
2347 | .in 1n | |
94e9d9fe | 2348 | sl local_address rem_address st tx_queue rx_queue tr rexmits tm\->when uid |
fea681da MK |
2349 | 1: 01642C89:0201 0C642C89:03FF 01 00000000:00000001 01:000071BA 00000000 0 |
2350 | 1: 00000000:0801 00000000:0000 0A 00000000:00000000 00:00000000 6F000100 0 | |
2351 | 1: 00000000:0201 00000000:0000 0A 00000000:00000000 00:00000000 00000000 0 | |
2352 | .in | |
2353 | .ft | |
2354 | .fi | |
2355 | .TP | |
2356 | .I /proc/net/unix | |
008f1ecc | 2357 | Lists the UNIX domain sockets present within the system and their |
c13182ef MK |
2358 | status. |
2359 | The format is: | |
fea681da MK |
2360 | .nf |
2361 | .sp .5 | |
2362 | .ft CW | |
2363 | Num RefCount Protocol Flags Type St Path | |
2364 | 0: 00000002 00000000 00000000 0001 03 | |
2365 | 1: 00000001 00000000 00010000 0001 01 /dev/printer | |
2366 | .ft | |
2367 | .sp .5 | |
2368 | .fi | |
2369 | ||
6c04f928 MK |
2370 | Here "Num" is the kernel table slot number, "RefCount" is the number |
2371 | of users of the socket, "Protocol" is currently always 0, "Flags" | |
fea681da | 2372 | represent the internal kernel flags holding the status of the |
c13182ef | 2373 | socket. |
008f1ecc | 2374 | Currently, type is always "1" (UNIX domain datagram sockets are |
6c04f928 MK |
2375 | not yet supported in the kernel). |
2376 | \&"St" is the internal state of the | |
fea681da MK |
2377 | socket and Path is the bound path (if any) of the socket. |
2378 | .TP | |
2379 | .I /proc/partitions | |
f042d149 MK |
2380 | Contains the major and minor numbers of each partition as well as the number |
2381 | of 1024-byte blocks and the partition name. | |
fea681da MK |
2382 | .TP |
2383 | .I /proc/pci | |
2384 | This is a listing of all PCI devices found during kernel initialization | |
2385 | and their configuration. | |
2990d781 | 2386 | |
59a40ed7 MK |
2387 | This file has been deprecated in favor of a new |
2388 | .I /proc | |
2990d781 MK |
2389 | interface for PCI |
2390 | .RI ( /proc/bus/pci ). | |
2391 | It became optional in Linux 2.2 (available with | |
2392 | .B CONFIG_PCI_OLD_PROC | |
2393 | set at kernel compilation). | |
24b74457 | 2394 | It became once more nonoptionally enabled in Linux 2.4. |
2990d781 MK |
2395 | Next, it was deprecated in Linux 2.6 (still available with |
2396 | .B CONFIG_PCI_LEGACY_PROC | |
2397 | set), and finally removed altogether since Linux 2.6.17. | |
b4e9ee8f MK |
2398 | .\" FIXME /proc/sched_debug |
2399 | .\" .TP | |
2400 | .\" .IR /proc/sched_debug " (since Linux 2.6.23)" | |
69119dc7 | 2401 | .\" See also /proc/[pid]/sched |
caea7868 MK |
2402 | .TP |
2403 | .IR /proc/profile " (since Linux 2.4)" | |
2404 | This file is present only if the kernel was booted with the | |
2405 | .I profile=1 | |
2406 | command-line option. | |
2407 | It exposes kernel profiling information in a binary format for use by | |
2408 | .BR readprofile (1). | |
2409 | Writing (e.g., an empty string) to this file resets the profiling counters; | |
2410 | on some architectures, | |
2411 | writing a binary integer "profiling multiplier" of size | |
2412 | .IR sizeof(int) | |
8a3ac89a | 2413 | sets the profiling interrupt frequency. |
fea681da MK |
2414 | .TP |
2415 | .I /proc/scsi | |
59a40ed7 MK |
2416 | A directory with the |
2417 | .I scsi | |
2418 | mid-level pseudo-file and various SCSI low-level | |
2990d781 MK |
2419 | driver directories, |
2420 | which contain a file for each SCSI host in this system, all of | |
c13182ef MK |
2421 | which give the status of some part of the SCSI IO subsystem. |
2422 | These files contain ASCII structures and are, therefore, readable with | |
2990d781 | 2423 | .BR cat (1). |
fea681da | 2424 | |
c13182ef | 2425 | You can also write to some of the files to reconfigure the subsystem or |
59a40ed7 | 2426 | switch certain features on or off. |
fea681da MK |
2427 | .TP |
2428 | .I /proc/scsi/scsi | |
c13182ef | 2429 | This is a listing of all SCSI devices known to the kernel. |
59a40ed7 | 2430 | The listing is similar to the one seen during bootup. |
c13182ef | 2431 | scsi currently supports only the \fIadd-single-device\fP command which |
59a40ed7 MK |
2432 | allows root to add a hotplugged device to the list of known devices. |
2433 | ||
2434 | The command | |
2435 | .in +4n | |
2436 | .nf | |
2437 | ||
2438 | echo \(aqscsi add-single-device 1 0 5 0\(aq > /proc/scsi/scsi | |
fea681da | 2439 | |
59a40ed7 MK |
2440 | .fi |
2441 | .in | |
c13182ef MK |
2442 | will cause |
2443 | host scsi1 to scan on SCSI channel 0 for a device on ID 5 LUN 0. | |
2444 | If there | |
fea681da MK |
2445 | is already a device known on this address or the address is invalid, an |
2446 | error will be returned. | |
2447 | .TP | |
2448 | .I /proc/scsi/[drivername] | |
c13182ef MK |
2449 | \fI[drivername]\fP can currently be NCR53c7xx, aha152x, aha1542, aha1740, |
2450 | aic7xxx, buslogic, eata_dma, eata_pio, fdomain, in2000, pas16, qlogic, | |
2451 | scsi_debug, seagate, t128, u15-24f, ultrastore, or wd7000. | |
2452 | These directories show up for all drivers that registered at least one | |
59a40ed7 | 2453 | SCSI HBA. |
c13182ef | 2454 | Every directory contains one file per registered host. |
59a40ed7 | 2455 | Every host-file is named after the number the host was assigned during |
c13182ef | 2456 | initialization. |
fea681da | 2457 | |
c13182ef | 2458 | Reading these files will usually show driver and host configuration, |
f78ed33a | 2459 | statistics, and so on. |
fea681da MK |
2460 | |
2461 | Writing to these files allows different things on different hosts. | |
2462 | For example, with the \fIlatency\fP and \fInolatency\fP commands, | |
2463 | root can switch on and off command latency measurement code in the | |
c13182ef MK |
2464 | eata_dma driver. |
2465 | With the \fIlockup\fP and \fIunlock\fP commands, | |
2466 | root can control bus lockups simulated by the scsi_debug driver. | |
fea681da MK |
2467 | .TP |
2468 | .I /proc/self | |
59a40ed7 MK |
2469 | This directory refers to the process accessing the |
2470 | .I /proc | |
9ee4a2b6 | 2471 | filesystem, |
59a40ed7 MK |
2472 | and is identical to the |
2473 | .I /proc | |
2474 | directory named by the process ID of the same process. | |
fea681da MK |
2475 | .TP |
2476 | .I /proc/slabinfo | |
c13182ef | 2477 | Information about kernel caches. |
90878f7c | 2478 | Since Linux 2.6.16 this file is present only if the |
821643a8 MK |
2479 | .B CONFIG_SLAB |
2480 | kernel configuration option is enabled. | |
350038ff | 2481 | The columns in |
38f76cd2 | 2482 | .I /proc/slabinfo |
350038ff | 2483 | are: |
a08ea57c | 2484 | .in +4n |
fea681da | 2485 | .nf |
a08ea57c | 2486 | |
fea681da MK |
2487 | cache-name |
2488 | num-active-objs | |
2489 | total-objs | |
2490 | object-size | |
2491 | num-active-slabs | |
2492 | total-slabs | |
2493 | num-pages-per-slab | |
2494 | .fi | |
a08ea57c MK |
2495 | .in |
2496 | ||
c13182ef | 2497 | See |
fea681da MK |
2498 | .BR slabinfo (5) |
2499 | for details. | |
2500 | .TP | |
2501 | .I /proc/stat | |
c13182ef MK |
2502 | kernel/system statistics. |
2503 | Varies with architecture. | |
2504 | Common | |
fea681da MK |
2505 | entries include: |
2506 | .RS | |
2507 | .TP | |
2508 | \fIcpu 3357 0 4313 1362393\fP | |
bfbfcd18 | 2509 | The amount of time, measured in units of |
268f000b MK |
2510 | USER_HZ (1/100ths of a second on most architectures, use |
2511 | .IR sysconf(_SC_CLK_TCK) | |
2512 | to obtain the right value), | |
b81087ab | 2513 | .\" 1024 on Alpha and ia64 |
ae3b8047 MK |
2514 | that the system spent in various states: |
2515 | .RS | |
2516 | .TP | |
2517 | .I user | |
ea0841f6 | 2518 | (1) Time spent in user mode. |
ae3b8047 MK |
2519 | .TP |
2520 | .I nice | |
0633f951 | 2521 | (2) Time spent in user mode with low priority (nice). |
9f1b9726 | 2522 | .TP |
ae3b8047 | 2523 | .I system |
0633f951 | 2524 | (3) Time spent in system mode. |
ae3b8047 MK |
2525 | .TP |
2526 | .I idle | |
ea0841f6 | 2527 | (4) Time spent in the idle task. |
b09b8526 | 2528 | .\" FIXME Actually, the following info about the /proc/stat 'cpu' field |
e04a1f93 MK |
2529 | .\" does not seem to be quite right (at least in 2.6.12 or 3.6): |
2530 | .\" the idle time in /proc/uptime does not quite match this value | |
2531 | This value should be USER_HZ times the | |
4cb1deb7 MK |
2532 | second entry in the |
2533 | .I /proc/uptime | |
2534 | pseudo-file. | |
ae3b8047 MK |
2535 | .TP |
2536 | .IR iowait " (since Linux 2.5.41)" | |
ea0841f6 | 2537 | (5) Time waiting for I/O to complete. |
ae3b8047 MK |
2538 | .TP |
2539 | .IR irq " (since Linux 2.6.0-test4)" | |
ea0841f6 | 2540 | (6) Time servicing interrupts. |
ae3b8047 | 2541 | .TP |
0633f951 | 2542 | .IR softirq " (since Linux 2.6.0-test4)" |
ea0841f6 | 2543 | (7) Time servicing softirqs. |
ae3b8047 MK |
2544 | .TP |
2545 | .IR steal " (since Linux 2.6.11)" | |
ea0841f6 | 2546 | (8) Stolen time, which is the time spent in other operating systems when |
9de1f6cc | 2547 | running in a virtualized environment |
ae3b8047 MK |
2548 | .TP |
2549 | .IR guest " (since Linux 2.6.24)" | |
0633f951 | 2550 | (9) Time spent running a virtual CPU for guest |
afef1764 | 2551 | operating systems under the control of the Linux kernel. |
14c06953 | 2552 | .\" See Changelog entry for 5e84cfde51cf303d368fcb48f22059f37b3872de |
d4fd4120 MK |
2553 | .TP |
2554 | .IR guest_nice " (since Linux 2.6.33)" | |
2555 | .\" commit ce0e7b28fb75cb003cfc8d0238613aaf1c55e797 | |
2556 | (10) Time spent running a niced guest (virtual CPU for guest | |
2557 | operating systems under the control of the Linux kernel). | |
ae3b8047 | 2558 | .RE |
fea681da MK |
2559 | .TP |
2560 | \fIpage 5741 1808\fP | |
2561 | The number of pages the system paged in and the number that were paged | |
2562 | out (from disk). | |
2563 | .TP | |
2564 | \fIswap 1 0\fP | |
2565 | The number of swap pages that have been brought in and out. | |
2566 | .TP | |
c13182ef | 2567 | .\" FIXME The following is not the full picture for the 'intr' of |
777f5a9e | 2568 | .\" /proc/stat on 2.6: |
fea681da | 2569 | \fIintr 1462898\fP |
bfbfcd18 MK |
2570 | This line shows counts of interrupts serviced since boot time, |
2571 | for each of the possible system interrupts. | |
d63ff76e | 2572 | The first column is the total of all interrupts serviced |
d6a56978 MK |
2573 | including unnumbered architecture specific interrupts; |
2574 | each subsequent column is the total for that particular numbered interrupt. | |
d63ff76e | 2575 | Unnumbered interrupts are not shown, only summed into the total. |
fea681da MK |
2576 | .TP |
2577 | \fIdisk_io: (2,0):(31,30,5764,1,2) (3,0):\fP... | |
636297e9 | 2578 | (major,disk_idx):(noinfo, read_io_ops, blks_read, write_io_ops, blks_written) |
bfbfcd18 MK |
2579 | .br |
2580 | (Linux 2.4 only) | |
fea681da MK |
2581 | .TP |
2582 | \fIctxt 115315\fP | |
2583 | The number of context switches that the system underwent. | |
2584 | .TP | |
2585 | \fIbtime 769041601\fP | |
f49c451a | 2586 | boot time, in seconds since the Epoch, 1970-01-01 00:00:00 +0000 (UTC). |
fea681da MK |
2587 | .TP |
2588 | \fIprocesses 86031\fP | |
2589 | Number of forks since boot. | |
bfbfcd18 MK |
2590 | .TP |
2591 | \fIprocs_running 6\fP | |
2592 | Number of processes in runnable state. | |
5fab2e7c | 2593 | (Linux 2.5.45 onward.) |
bfbfcd18 MK |
2594 | .TP |
2595 | \fIprocs_blocked 2\fP | |
2596 | Number of processes blocked waiting for I/O to complete. | |
5fab2e7c | 2597 | (Linux 2.5.45 onward.) |
fea681da MK |
2598 | .RE |
2599 | .TP | |
2600 | .I /proc/swaps | |
c13182ef MK |
2601 | Swap areas in use. |
2602 | See also | |
fea681da MK |
2603 | .BR swapon (8). |
2604 | .TP | |
2605 | .I /proc/sys | |
2606 | This directory (present since 1.3.57) contains a number of files | |
2607 | and subdirectories corresponding to kernel variables. | |
2608 | These variables can be read and sometimes modified using | |
9ee4a2b6 | 2609 | the \fI/proc\fP filesystem, and the (deprecated) |
fea681da | 2610 | .BR sysctl (2) |
c13182ef | 2611 | system call. |
fea681da | 2612 | .TP |
6ab7c0aa | 2613 | .IR /proc/sys/abi " (since Linux 2.4.10)" |
fea681da | 2614 | This directory may contain files with application binary information. |
6ab7c0aa | 2615 | .\" On some systems, it is not present. |
66a9882e | 2616 | See the Linux kernel source file |
6ab7c0aa MK |
2617 | .I Documentation/sysctl/abi.txt |
2618 | for more information. | |
fea681da MK |
2619 | .TP |
2620 | .I /proc/sys/debug | |
2621 | This directory may be empty. | |
2622 | .TP | |
2623 | .I /proc/sys/dev | |
e2badfdf | 2624 | This directory contains device-specific information (e.g., |
9a67332e | 2625 | .IR dev/cdrom/info ). |
fea681da MK |
2626 | On |
2627 | some systems, it may be empty. | |
2628 | .TP | |
2629 | .I /proc/sys/fs | |
49236d3c | 2630 | This directory contains the files and subdirectories for kernel variables |
9ee4a2b6 | 2631 | related to filesystems. |
fea681da MK |
2632 | .TP |
2633 | .I /proc/sys/fs/binfmt_misc | |
c13182ef | 2634 | Documentation for files in this directory can be found |
66a9882e | 2635 | in the Linux kernel sources in |
fea681da MK |
2636 | .IR Documentation/binfmt_misc.txt . |
2637 | .TP | |
59a40ed7 MK |
2638 | .IR /proc/sys/fs/dentry-state " (since Linux 2.2)" |
2639 | This file contains information about the status of the | |
2640 | directory cache (dcache). | |
2641 | The file contains six numbers, | |
c13182ef | 2642 | .IR nr_dentry ", " nr_unused ", " age_limit " (age in seconds), " |
59a40ed7 | 2643 | .I want_pages |
fea681da | 2644 | (pages requested by system) and two dummy values. |
59a40ed7 MK |
2645 | .RS |
2646 | .IP * 2 | |
2647 | .I nr_dentry | |
2648 | is the number of allocated dentries (dcache entries). | |
2649 | This field is unused in Linux 2.2. | |
2650 | .IP * | |
2651 | .I nr_unused | |
2652 | is the number of unused dentries. | |
2653 | .IP * | |
2654 | .I age_limit | |
2655 | .\" looks like this is unused in kernels 2.2 to 2.6 | |
2656 | is the age in seconds after which dcache entries | |
2657 | can be reclaimed when memory is short. | |
2658 | .IP * | |
2659 | .I want_pages | |
2660 | .\" looks like this is unused in kernels 2.2 to 2.6 | |
c7094399 | 2661 | is nonzero when the kernel has called shrink_dcache_pages() and the |
fea681da | 2662 | dcache isn't pruned yet. |
59a40ed7 | 2663 | .RE |
fea681da MK |
2664 | .TP |
2665 | .I /proc/sys/fs/dir-notify-enable | |
2666 | This file can be used to disable or enable the | |
2667 | .I dnotify | |
2668 | interface described in | |
2669 | .BR fcntl (2) | |
2670 | on a system-wide basis. | |
2671 | A value of 0 in this file disables the interface, | |
2672 | and a value of 1 enables it. | |
2673 | .TP | |
2674 | .I /proc/sys/fs/dquot-max | |
2675 | This file shows the maximum number of cached disk quota entries. | |
2676 | On some (2.4) systems, it is not present. | |
2677 | If the number of free cached disk quota entries is very low and | |
2678 | you have some awesome number of simultaneous system users, | |
2679 | you might want to raise the limit. | |
2680 | .TP | |
2681 | .I /proc/sys/fs/dquot-nr | |
2682 | This file shows the number of allocated disk quota | |
2683 | entries and the number of free disk quota entries. | |
2684 | .TP | |
24cb4a4b | 2685 | .IR /proc/sys/fs/epoll " (since Linux 2.6.28)" |
242b46af MK |
2686 | This directory contains the file |
2687 | .IR max_user_watches , | |
24cb4a4b MK |
2688 | which can be used to limit the amount of kernel memory consumed by the |
2689 | .I epoll | |
2690 | interface. | |
2691 | For further details, see | |