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perf-kmem(1) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | SEE ALSO | COLOPHON 

PERF-KMEM(1)                   perf Manual                   PERF-KMEM(1)

NAME         top

       perf-kmem - Tool to trace/measure kernel memory properties

SYNOPSIS         top

       perf kmem [<options>] {record|stat}

DESCRIPTION         top

       There are two variants of perf kmem:

           'perf kmem [<options>] record [<perf-record-options>] <command>' to
           record the kmem events of an arbitrary workload. Additional 'perf
           record' options may be specified after record, such as '-o' to
           change the output file name.

           'perf kmem [<options>] stat' to report kernel memory statistics.

OPTIONS         top

       -i <file>, --input=<file>
           For stat, select the input file (default: perf.data unless
           stdin is a fifo)

       -f, --force
           Don’t do ownership validation

       -v, --verbose
           Be more verbose. (show symbol address, etc)

       --caller
           Show per-callsite statistics

       --alloc
           Show per-allocation statistics

       -s <key[,key2...]>, --sort=<key[,key2...]>
           Sort the output (default: frag,hit,bytes for slab and
           bytes,hit for page). Available sort keys are ptr, callsite,
           bytes, hit, pingpong, frag for slab and page, callsite, bytes,
           hit, order, migtype, gfp for page. This option should be
           preceded by one of the mode selection options - i.e. --slab,
           --page, --alloc and/or --caller.

       -l <num>, --line=<num>
           Print n lines only

       --raw-ip
           Print raw ip instead of symbol

       --slab
           Analyze SLAB allocator events.

       --page
           Analyze page allocator events

       --live
           Show live page stat. The perf kmem shows total allocation stat
           by default, but this option shows live (currently allocated)
           pages instead. (This option works with --page option only)

       --time=<start>,<stop>
           Only analyze samples within given time window: <start>,<stop>.
           Times have the format seconds.microseconds. If start is not
           given (i.e., time string is ,x.y) then analysis starts at the
           beginning of the file. If stop time is not given (i.e, time
           string is x.y,) then analysis goes to end of file.

SEE ALSO         top

       perf-record(1)

COLOPHON         top

       This page is part of the perf (Performance analysis tools for
       Linux (in Linux source tree)) project.  Information about the
       project can be found at 
       ⟨https://perf.wiki.kernel.org/index.php/Main_Page⟩.  If you have a
       bug report for this manual page, send it to
       linux-kernel@vger.kernel.org.  This page was obtained from the
       project's upstream Git repository
       ⟨http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git⟩
       on 2025-02-02.  (At that time, the date of the most recent commit
       that was found in the repository was 2025-02-01.)  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

perf                            2021-10-08                   PERF-KMEM(1)

Pages that refer to this page: perf(1)

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