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Namhyung Kim 0bf02a0d80 perf bench: Add build-id injection benchmark
Sometimes I can see that 'perf record' piped with 'perf inject' take a
long time processing build-ids.

So introduce a inject-build-id benchmark to the internals benchmark
suite to measure its overhead regularly.

It runs the 'perf inject' command internally and feeds the given number
of synthesized events (MMAP2 + SAMPLE basically).

  Usage: perf bench internals inject-build-id <options>

    -i, --iterations <n>  Number of iterations used to compute average (default: 100)
    -m, --nr-mmaps <n>    Number of mmap events for each iteration (default: 100)
    -n, --nr-samples <n>  Number of sample events per mmap event (default: 100)
    -v, --verbose         be more verbose (show iteration count, DSO name, etc)

By default, it measures average processing time of 100 MMAP2 events
and 10000 SAMPLE events.  Below is a result on my laptop.

  $ perf bench internals inject-build-id
  # Running 'internals/inject-build-id' benchmark:
    Average build-id injection took: 25.789 msec (+- 0.202 msec)
    Average time per event: 2.528 usec (+- 0.020 usec)
    Average memory usage: 8411 KB (+- 7 KB)

Committer testing:

  $ perf bench
  Usage:
  	perf bench [<common options>] <collection> <benchmark> [<options>]

          # List of all available benchmark collections:

           sched: Scheduler and IPC benchmarks
         syscall: System call benchmarks
             mem: Memory access benchmarks
            numa: NUMA scheduling and MM benchmarks
           futex: Futex stressing benchmarks
           epoll: Epoll stressing benchmarks
       internals: Perf-internals benchmarks
             all: All benchmarks

  $ perf bench internals

          # List of available benchmarks for collection 'internals':

      synthesize: Benchmark perf event synthesis
  kallsyms-parse: Benchmark kallsyms parsing
  inject-build-id: Benchmark build-id injection

  $ perf bench internals inject-build-id
  # Running 'internals/inject-build-id' benchmark:
    Average build-id injection took: 14.202 msec (+- 0.059 msec)
    Average time per event: 1.392 usec (+- 0.006 usec)
    Average memory usage: 12650 KB (+- 10 KB)
    Average build-id-all injection took: 12.831 msec (+- 0.071 msec)
    Average time per event: 1.258 usec (+- 0.007 usec)
    Average memory usage: 11895 KB (+- 10 KB)
  $

  $ perf stat -r5 perf bench internals inject-build-id
  # Running 'internals/inject-build-id' benchmark:
    Average build-id injection took: 14.380 msec (+- 0.056 msec)
    Average time per event: 1.410 usec (+- 0.006 usec)
    Average memory usage: 12608 KB (+- 11 KB)
    Average build-id-all injection took: 11.889 msec (+- 0.064 msec)
    Average time per event: 1.166 usec (+- 0.006 usec)
    Average memory usage: 11838 KB (+- 10 KB)
  # Running 'internals/inject-build-id' benchmark:
    Average build-id injection took: 14.246 msec (+- 0.065 msec)
    Average time per event: 1.397 usec (+- 0.006 usec)
    Average memory usage: 12744 KB (+- 10 KB)
    Average build-id-all injection took: 12.019 msec (+- 0.066 msec)
    Average time per event: 1.178 usec (+- 0.006 usec)
    Average memory usage: 11963 KB (+- 10 KB)
  # Running 'internals/inject-build-id' benchmark:
    Average build-id injection took: 14.321 msec (+- 0.067 msec)
    Average time per event: 1.404 usec (+- 0.007 usec)
    Average memory usage: 12690 KB (+- 10 KB)
    Average build-id-all injection took: 11.909 msec (+- 0.041 msec)
    Average time per event: 1.168 usec (+- 0.004 usec)
    Average memory usage: 11938 KB (+- 10 KB)
  # Running 'internals/inject-build-id' benchmark:
    Average build-id injection took: 14.287 msec (+- 0.059 msec)
    Average time per event: 1.401 usec (+- 0.006 usec)
    Average memory usage: 12864 KB (+- 10 KB)
    Average build-id-all injection took: 11.862 msec (+- 0.058 msec)
    Average time per event: 1.163 usec (+- 0.006 usec)
    Average memory usage: 12103 KB (+- 10 KB)
  # Running 'internals/inject-build-id' benchmark:
    Average build-id injection took: 14.402 msec (+- 0.053 msec)
    Average time per event: 1.412 usec (+- 0.005 usec)
    Average memory usage: 12876 KB (+- 10 KB)
    Average build-id-all injection took: 11.826 msec (+- 0.061 msec)
    Average time per event: 1.159 usec (+- 0.006 usec)
    Average memory usage: 12111 KB (+- 10 KB)

   Performance counter stats for 'perf bench internals inject-build-id' (5 runs):

            4,267.48 msec task-clock:u              #    1.502 CPUs utilized            ( +-  0.14% )
                   0      context-switches:u        #    0.000 K/sec
                   0      cpu-migrations:u          #    0.000 K/sec
             102,092      page-faults:u             #    0.024 M/sec                    ( +-  0.08% )
       3,894,589,578      cycles:u                  #    0.913 GHz                      ( +-  0.19% )  (83.49%)
         140,078,421      stalled-cycles-frontend:u #    3.60% frontend cycles idle     ( +-  0.77% )  (83.34%)
         948,581,189      stalled-cycles-backend:u  #   24.36% backend cycles idle      ( +-  0.46% )  (83.25%)
       5,835,587,719      instructions:u            #    1.50  insn per cycle
                                                    #    0.16  stalled cycles per insn  ( +-  0.21% )  (83.24%)
       1,267,423,636      branches:u                #  296.996 M/sec                    ( +-  0.22% )  (83.12%)
          17,484,290      branch-misses:u           #    1.38% of all branches          ( +-  0.12% )  (83.55%)

             2.84176 +- 0.00222 seconds time elapsed  ( +-  0.08% )

  $

Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20201012070214.2074921-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-10-13 10:59:42 -03:00
Documentation Kbuild fixes for v5.9 (4th) 2020-09-27 12:18:57 -07:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
arch Two fixes for the x86 interrupt code: 2020-09-27 12:15:21 -07:00
block SCSI fixes on 20200926 2020-09-26 11:18:37 -07:00
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crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2020-08-30 15:53:44 -07:00
drivers A set of clocksource/clockevents updates: 2020-09-27 12:11:35 -07:00
fs NFS client bugfixes for Linux 5.9 2020-09-28 11:05:56 -07:00
include NFS client bugfixes for Linux 5.9 2020-09-28 11:05:56 -07:00
init bootconfig: init: make xbc_namebuf static 2020-09-18 22:17:05 -04:00
ipc ipc: adjust proc_ipc_sem_dointvec definition to match prototype 2020-09-05 12:14:29 -07:00
kernel mm/fork: Pass new vma pointer into copy_page_range() 2020-09-27 11:21:35 -07:00
lib lib/memregion.c: include memregion.h 2020-09-26 10:33:57 -07:00
mm mm: do not rely on mm == current->mm in __get_user_pages_locked 2020-09-28 09:21:50 -07:00
net Fixes: 2020-09-25 10:46:11 -07:00
samples treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
scripts scripts/kallsyms: skip ppc compiler stub *.long_branch.* / *.plt_branch.* 2020-09-25 00:41:54 +09:00
security device_cgroup RCU warning fix from Amol Grover <frextrite@gmail.com> 2020-09-15 16:26:57 -07:00
sound sound fixes for 5.9-rc7 2020-09-24 09:00:05 -07:00
tools perf bench: Add build-id injection benchmark 2020-10-13 10:59:42 -03:00
usr Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
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README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.