LSMEM(1)                                User Commands                               LSMEM(1)

NAME
       lsmem - list the ranges of available memory with their online status

SYNOPSIS
       lsmem [options]

DESCRIPTION
       The  lsmem command lists the ranges of available memory with their online status. The
       listed memory blocks correspond to the memory block representation in sysfs. The com‐
       mand  also shows the memory block size and the amount of memory in online and offline
       state.

       The default output compatible with original implementation from s390-tools, but  it's
       strongly  recommended to avoid using default outputs in your scripts.  Always explic‐
       itly define expected columns by using the --output option  together  with  a  columns
       list in environments where a stable output is required.

       The  lsmem command lists a new memory range always when the current memory block dis‐
       tinguish from the previous block by some output column.   This  default  behavior  is
       possible  to  override by the --split option (e.g. lsmem --split=ZONES).  The special
       word "none" may be used to ignore all differences between memory blocks and to create
       as large as possible continuous ranges.  The opposite semantic is --all to list indi‐
       vidual memory blocks.

       Note that some output columns may provide inaccurate information if  a  split  policy
       forces  lsmem  to ignore differences in some attributes. For example if you merge re‐
       movable and non-removable memory blocks to the one range than all the range  will  be
       marked as non-removable on lsmem output.

       Not all columns are supported on all systems.  If an unsupported column is specified,
       lsmem prints the column but does not provide any data for it.

       Use the --help option to see the columns description.

OPTIONS
       -a, --all
              List each individual memory block, instead of  combining  memory  blocks  with
              similar attributes.

       -b, --bytes
              Print the SIZE column in bytes rather than in a human-readable format.

       -h, --help
              Display help text and exit.

       -J, --json
              Use JSON output format.

       -n, --noheadings
              Do not print a header line.

       -o, --output list
              Specify  which  output columns to print.  Use --help to get a list of all sup‐
              ported columns.  The default list of columns may be extended if list is speci‐
              fied in the format +list (e.g. lsmem -o +NODE).

       --output-all
              Output all available columns.

       -P, --pairs
              Produce output in the form of key="value" pairs.  All potentially unsafe char‐
              acters are hex-escaped (\x<code>).

       -r, --raw
              Produce output in raw format.  All potentially unsafe characters  are  hex-es‐
              caped (\x<code>).

       -S, --split list
              Specify  which columns (attributes) use to split memory blocks to ranges.  The
              supported columns are STATE, REMOVABLE, NODE and ZONES, or "none". The another
              columns are silently ignored. For more details see DESCRIPTION above.

       -s, --sysroot directory
              Gather memory data for a Linux instance other than the instance from which the
              lsmem command is issued.  The specified directory is the system  root  of  the
              Linux instance to be inspected.

       -V, --version
              Display version information and exit.

       --summary[=when]
              This  option controls summary lines output.  The optional argument when can be
              never, always or only.  If the  when  argument  is  omitted,  it  defaults  to
              "only". The summary output is suppressed for --raw, --pairs and --json.

AUTHOR
       lsmem was originally written by Gerald Schaefer for s390-tools in Perl. The C version
       for util-linux was written by Clemens von Mann, Heiko Carstens and Karel Zak.

SEE ALSO
       chmem(8)

AVAILABILITY
       The lsmem command is part of the util-linux  package  and  is  available  from  Linux
       Kernel Archive ⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩.

util-linux                              October 2016                                LSMEM(1)

Usage:
 lsmem [options]

List the ranges of available memory with their online status.

Options:
 -J, --json           use JSON output format
 -P, --pairs          use key="value" output format
 -a, --all            list each individual memory block
 -b, --bytes          print SIZE in bytes rather than in human readable format
 -n, --noheadings     don't print headings
 -o, --output <list>  output columns
     --output-all     output all columns
 -r, --raw            use raw output format
 -S, --split <list>   split ranges by specified columns
 -s, --sysroot <dir>  use the specified directory as system root
     --summary[=when] print summary information (never,always or only)

 -h, --help           display this help
 -V, --version        display version

Available output columns:
      RANGE  start and end address of the memory range
       SIZE  size of the memory range
      STATE  online status of the memory range
  REMOVABLE  memory is removable
      BLOCK  memory block number or blocks range
       NODE  numa node of memory
      ZONES  valid zones for the memory range

For more details see lsmem(1).