|
HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|
|
NAME | SYNTAX | DESCRIPTION | OPTIONS | NOTES | ENVIRONMENT VARIABLES | FILES | EXAMPLES | AUTHORS | SEE ALSO | COLOPHON |
|
|
|
numastat(8) Administration numastat(8)
numastat - Show per-NUMA-node memory statistics for processes and
the operating system
numastat
numastat [-V]
numastat [<PID>|<pattern>...]
numastat [-c] [-m] [-n] [-p <PID>|<pattern>] [-s[<node>]] [-v]
[-z] [<PID>|<pattern>...]
numastat with no command options or arguments at all, displays
per-node NUMA hit and miss system statistics from the kernel
memory allocator. This default numastat behavior is strictly
compatible with the previous long-standing numastat perl script,
written by Andi Kleen. The default numastat statistics shows per-
node numbers (in units of pages of memory) in these categories:
numa_hit is memory successfully allocated on this node as
intended.
numa_miss is memory allocated on this node despite the process
preferring some different node. Each numa_miss has a numa_foreign
on another node.
numa_foreign is memory intended for this node, but actually
allocated on some different node. Each numa_foreign has a
numa_miss on another node.
interleave_hit is interleaved memory successfully allocated on
this node as intended.
local_node is memory allocated on this node while a process was
running on it.
other_node is memory allocated on this node while a process was
running on some other node.
Any supplied options or arguments with the numastat command will
significantly change both the content and the format of the
display. Specified options will cause display units to change to
megabytes of memory, and will change other specific behaviors of
numastat as described below.
Memory usage information reflects the resident pages on the
system.
-c Minimize table display width by dynamically shrinking
column widths based on data contents. With this option,
amounts of memory will be rounded to the nearest megabyte
(rather than the usual display with two decimal places).
Column width and inter-column spacing will be somewhat
unpredictable with this option, but the more dense display
will be very useful on systems with many NUMA nodes.
-m Show the meminfo-like system-wide memory usage information.
This option produces a per-node breakdown of memory usage
information similar to that found in /proc/meminfo.
-n Show the original numastat statistics info. This will show
the same information as the default numastat behavior but
the units will be megabytes of memory, and there will be
other formatting and layout changes versus the original
numastat behavior.
-p <PID> or <pattern>
Show per-node memory allocation information for the
specified PID or pattern. If the -p argument is only
digits, it is assumed to be a numerical PID. If the
argument characters are not only digits, it is assumed to
be a text fragment pattern to search for in process command
lines. For example, numastat -p qemu will attempt to find
and show information for processes with "qemu" in the
command line. Any command line arguments remaining after
numastat option flag processing is completed, are assumed
to be additional <PID> or <pattern> process specifiers. In
this sense, the -p option flag is optional: numastat qemu
is equivalent to numastat -p qemu
-s[<node>]
Sort the table data in descending order before displaying
it, so the biggest memory consumers are listed first. With
no specified <node>, the table will be sorted by the total
column. If the optional <node> argument is supplied, the
data will be sorted by the <node> column. Note that <node>
must follow the -s immediately with no intermediate white
space (e.g., numastat -s2). Because -s can allow an
optional argument, it must always be the last option
character in a compound option character string. For
example, instead of numastat -msc (which probably will not
work as you expect), use numastat -mcs
-v Make some reports more verbose. In particular, process
information for multiple processes will display detailed
information for each process. Normally when per-node
information for multiple processes is displayed, only the
total lines are shown.
-V Display numastat version information and exit.
-z Skip display of table rows and columns of only zero
valuess. This can be used to greatly reduce the amount of
uninteresting zero data on systems with many NUMA nodes.
Note that when rows or columns of zeros are still displayed
with this option, that probably means there is at least one
value in the row or column that is actually non-zero, but
rounded to zero for display.
numastat attempts to fold each table display so it will be
conveniently readable on the output terminal. Normally a terminal
width of 80 characters is assumed. When the resize command is
available, numastat attempts to dynamically determine and fine
tune the output tty width from resize output. If numastat output
is not to a tty, very long output lines can be produced, depending
on how many NUMA nodes are present. In all cases, output width
can be explicitly specified via the NUMASTAT_WIDTH environment
variable. For example, NUMASTAT_WIDTH=100 numastat. On systems
with many NUMA nodes, numastat -c -z .... can be very helpful to
selectively reduce the amount of displayed information.
NUMASTAT_WIDTH
/proc/*/numa_maps
/sys/devices/system/node/node*/meminfo
/sys/devices/system/node/node*/numastat
numastat -c -z -m -n
numastat -czs libvirt kvm qemu
watch -n1 numastat
watch -n1 --differences=cumulative numastat
The original numastat perl script was written circa 2003 by Andi
Kleen <andi.kleen@intel.com>. The current numastat program was
written in 2012 by Bill Gray <bgray@redhat.com> to be compatible
by default with the original, and to add options to display per-
node system memory usage and per-node process memory allocation.
numactl(8), set_mempolicy(2), numa(3)
This page is part of the numactl (NUMA commands) project.
Information about the project can be found at
⟨http://oss.sgi.com/projects/libnuma/⟩. If you have a bug report
for this manual page, send it to linux-numa@vger.kernel.org. This
page was obtained from the project's upstream Git repository
⟨https://github.com/numactl/numactl.git⟩ on 2025-08-11. (At that
time, the date of the most recent commit that was found in the
repository was 2025-08-04.) If you discover any rendering
problems in this HTML version of the page, or you believe there is
a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
man-pages@man7.org
Bill Gray 1.0.0 numastat(8)
Pages that refer to this page: migrate_pages(2), move_pages(2)
|
HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|