linux/tools/perf/Documentation/perf-kmem.txt
Namhyung Kim 0d68bc92c4 perf kmem: Analyze page allocator events also
The perf kmem command records and analyze kernel memory allocation only
for SLAB objects.  This patch implement a simple page allocator analyzer
using kmem:mm_page_alloc and kmem:mm_page_free events.

It adds two new options of --slab and --page.  The --slab option is for
analyzing SLAB allocator and that's what perf kmem currently does.

The new --page option enables page allocator events and analyze kernel
memory usage in page unit.  Currently, 'stat --alloc' subcommand is
implemented only.

If none of these --slab nor --page is specified, --slab is implied.

First run 'perf kmem record' to generate a suitable perf.data file:

  # perf kmem record --page sleep 5

Then run 'perf kmem stat' to postprocess the perf.data file:

  # perf kmem stat --page --alloc --line 10

  -------------------------------------------------------------------------------
   PFN              | Total alloc (KB) | Hits     | Order | Mig.type | GFP flags
  -------------------------------------------------------------------------------
            4045014 |               16 |        1 |     2 |  RECLAIM |  00285250
            4143980 |               16 |        1 |     2 |  RECLAIM |  00285250
            3938658 |               16 |        1 |     2 |  RECLAIM |  00285250
            4045400 |               16 |        1 |     2 |  RECLAIM |  00285250
            3568708 |               16 |        1 |     2 |  RECLAIM |  00285250
            3729824 |               16 |        1 |     2 |  RECLAIM |  00285250
            3657210 |               16 |        1 |     2 |  RECLAIM |  00285250
            4120750 |               16 |        1 |     2 |  RECLAIM |  00285250
            3678850 |               16 |        1 |     2 |  RECLAIM |  00285250
            3693874 |               16 |        1 |     2 |  RECLAIM |  00285250
   ...              | ...              | ...      | ...   | ...      | ...
  -------------------------------------------------------------------------------

  SUMMARY (page allocator)
  ========================
  Total allocation requests     :           44,260   [          177,256 KB ]
  Total free requests           :              117   [              468 KB ]

  Total alloc+freed requests    :               49   [              196 KB ]
  Total alloc-only requests     :           44,211   [          177,060 KB ]
  Total free-only requests      :               68   [              272 KB ]

  Total allocation failures     :                0   [                0 KB ]

  Order     Unmovable   Reclaimable       Movable      Reserved  CMA/Isolated
  -----  ------------  ------------  ------------  ------------  ------------
      0            32             .        44,210             .             .
      1             .             .             .             .             .
      2             .            18             .             .             .
      3             .             .             .             .             .
      4             .             .             .             .             .
      5             .             .             .             .             .
      6             .             .             .             .             .
      7             .             .             .             .             .
      8             .             .             .             .             .
      9             .             .             .             .             .
     10             .             .             .             .             .

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/1428298576-9785-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-13 11:44:52 -03:00

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perf-kmem(1)
============
NAME
----
perf-kmem - Tool to trace/measure kernel memory properties
SYNOPSIS
--------
[verse]
'perf kmem' {record|stat} [<options>]
DESCRIPTION
-----------
There are two variants of perf kmem:
'perf kmem record <command>' to record the kmem events
of an arbitrary workload.
'perf kmem stat' to report kernel memory statistics.
OPTIONS
-------
-i <file>::
--input=<file>::
Select the input file (default: perf.data unless stdin is a fifo)
-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)
-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
SEE ALSO
--------
linkperf:perf-record[1]