sys-utils/zramctl.8

   1 .TH ZRAMCTL 8 "July 2014" "util-linux" "System Administration"
   2 .SH NAME
   3 zramctl \- set up and control zram devices
   4 .SH SYNOPSIS
   5 .ad l
   6 Get info:
   7 .sp
   8 .in +5
   9 .BR zramctl " [options]"
  10 .sp
  11 .in -5
  12 Reset zram:
  13 .sp
  14 .in +5
  15 .B "zramctl \-r"
  16 .IR zramdev ...
  17 .sp
  18 .in -5
  19 Print name of first unused zram device:
  20 .sp
  21 .in +5
  22 .B "zramctl \-f"
  23 .sp
  24 .in -5
  25 Setup zram device:
  26 .sp
  27 .in +5
  28 .B zramctl
  29 .RB [ \-f " | "\fIzramdev\fP ]
  30 .RB [ \-s
  31 .IR size ]
  32 .RB \ [ \-t
  33 .IR number ]
  34 .in +8
  35 .RB [ \-a
  36 .IR algorithm ]
  37 .sp
  38 .in -13
  39 .ad b
  40 .SH DESCRIPTION
  41 .B zramctl
  42 is used to quickly set up zram device parameters, to reset zram devices, and to
  43 query the status of used zram devices.  If no option is given, all zram devices
  44 are shown.
  45
  46 .SH OPTIONS
  47 .IP "\fB\-a, \-\-algorithm \fI{lzo|lz4}\fP"
  48 Set compression algorithm used for compress data in zram device.
  49 .IP "\fB\-f, \-\-find\fP"
  50 Find the first unused zram device. If a \fB--size\fR argument is present, then
  51 initialize the device.
  52 .IP "\fB\-h, \-\-help\fP"
  53 print help
  54 .IP "\fB\-h, \-\-noheadings\fP"
  55 Do not print a header line in status output.
  56 .IP "\fB\-o, \-\-output \fIlist\fP"
  57 Define the status output columns to use.  If no output arrangement is specified,
  58 then a default set is used.
  59 Use \fB\-\-help\fP to get a list of all supported columns.
  60 .IP "\fB\-r, \-\-reset\fP
  61 Reset options specified zram device(s). Zram device setting can be changed only
  62 after reset.
  63 .IP "\fB\-\-raw\fP"
  64 Use the raw format for status output.
  65 .IP "\fB\-s, \-\-size\fP \fIsize\fP
  66 Force zram driver to reread size of the file associated with the specified zram device
  67
  68 The \fIsize\fR argument may be followed by the multiplicative suffixes KiB (=1024),
  69 MiB (=1024*1024), and so on for GiB, TiB, PiB, EiB, ZiB and YiB (the "iB"
  70 is optional, e.g., "K" has the same meaning as "KiB") or the suffixes
  71 KB (=1000), MB (=1000*1000), and so on for GB, TB, PB, EB, ZB and YB.
  72 .IP "\fB\-t, \-\-streams \fInumber\fP"
  73 Set number of maximum compress streams what used for device. The default is one stream.
  74 .IP "\fB\-V, \-\-version\fP"
  75 Display version information and exit.
  76
  77 .SH RETURN VALUE
  78 .B zramctl
  79 returns 0 on success, nonzero on failure.
  80
  81 .SH FILES
  82 .TP
  83 .I /dev/zram[0..N]
  84 zram block devices
  85
  86 .SH EXAMPLE
  87 The following commands can be used for setup the zram device with gigabyte size
  88  and using as swap device.
  89 .nf
  90 .IP
  91 # zramctl --find --size 1024M
  92 /dev/zram0
  93 # mkswap /dev/zram0
  94 # swapon /dev/zram0
  95  ...
  96 # swapoff /dev/zram0
  97 # zramctl --reset /dev/zram0
  98 .fi
  99 .SH AUTHORS
 100 .nf
 101 Timofey Titovets <nefelim4ag@gmail.com>
 102 Karel Zak <kzak@redhat.com>
 103 .fi
 104 .SH AVAILABILITY
 105 The zramctl command is part of the util-linux package and is available from
 106 ftp://ftp.kernel.org/pub/linux/utils/util-linux/.