Re: [PATCHSET v4 0/6] perf inject: Speed build-id injection

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Mon, Oct 12, 2020 at 04:02:08PM +0900, Namhyung Kim escreveu:
> Hello,
> 
> This is the new version of speed up build-id injection.  As this is
> to improve performance, I've added a benchmark for it.  Please look at
> the usage in the first commit.
> 
> By default, it measures average processing time of 100 MMAP2 events
> and 10000 SAMPLE events.  Below is the current 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)
> 
> With this patchset applied, it got this:
> 
>   $ perf bench internals inject-build-id
>   # Running 'internals/inject-build-id' benchmark:
>     Average build-id injection took: 20.838 msec (+- 0.093 msec)
>     Average time per event: 2.043 usec (+- 0.009 usec)
>     Average memory usage: 8261 KB (+- 0 KB)
>     Average build-id-all injection took: 19.361 msec (+- 0.118 msec)
>     Average time per event: 1.898 usec (+- 0.012 usec)
>     Average memory usage: 7440 KB (+- 0 KB)
> 
> 
> Real usecases might be different as it depends on the number of
> mmap/sample events as well as how many DSOs are actually hit.
> 
> The benchmark result now includes memory footprint in terms of maximum
> RSS.  Also I've update the benchmark code to use timestamp so that it
> can be queued to the ordered_events (and flushed at the end).  It's
> also important how well it sorts the input events in the queue so I
> randomly chose a timestamp at the beginning of each MMAP event
> injection to resemble actual behavior.
> 
> As I said in other thread, perf inject currently doesn't flush the
> input events and processes all at the end.  This gives a good speedup
> but spends more memory (in proprotion to the input size).  While the
> build-id-all injection bypasses the queue so it uses less memory as
> well as faster processing.  The downside is that it'll mark all DSOs
> as hit so later processing steps (like perf report) likely handle them
> unnecessarily.

Thanks, tested and applied, first patchkit I process using that b4 tool,
cool!

- Arnaldo
 
> 
> This code is available at 'perf/inject-speedup-v4' branch on
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git
> 
> 
> Changes from v3:
>  - add timestamp to the synthesized events in the benchmark
>  - add a separate thread to read pipe in the benchmark
> 
> Changes from v2:
>  - fix benchmark to read required data
>  - add Acked-by from Jiri and Ian
>  - pass map flag to check huge pages  (Jiri)
>  - add comments on some functions  (Ian)
>  - show memory (max-RSS) usage in the benchmark  (Ian)
>  - drop build-id marking patch at the last  (Adrian)
> 
> 
> Namhyung Kim (6):
>   perf bench: Add build-id injection benchmark
>   perf inject: Add missing callbacks in perf_tool
>   perf inject: Enter namespace when reading build-id
>   perf inject: Do not load map/dso when injecting build-id
>   perf inject: Add --buildid-all option
>   perf bench: Run inject-build-id with --buildid-all option too
> 
>  tools/perf/Documentation/perf-inject.txt |   6 +-
>  tools/perf/bench/Build                   |   1 +
>  tools/perf/bench/bench.h                 |   1 +
>  tools/perf/bench/inject-buildid.c        | 457 +++++++++++++++++++++++
>  tools/perf/builtin-bench.c               |   1 +
>  tools/perf/builtin-inject.c              | 199 ++++++++--
>  tools/perf/util/build-id.h               |   4 +
>  tools/perf/util/map.c                    |  17 +-
>  tools/perf/util/map.h                    |  14 +
>  9 files changed, 645 insertions(+), 55 deletions(-)
>  create mode 100644 tools/perf/bench/inject-buildid.c
> 
> -- 
> 2.28.0.681.g6f77f65b4e-goog
> 
> 
> *** BLURB HERE ***
> 
> Namhyung Kim (6):
>   perf bench: Add build-id injection benchmark
>   perf inject: Add missing callbacks in perf_tool
>   perf inject: Enter namespace when reading build-id
>   perf inject: Do not load map/dso when injecting build-id
>   perf inject: Add --buildid-all option
>   perf bench: Run inject-build-id with --buildid-all option too
> 
>  tools/perf/Documentation/perf-inject.txt |   6 +-
>  tools/perf/bench/Build                   |   1 +
>  tools/perf/bench/bench.h                 |   1 +
>  tools/perf/bench/inject-buildid.c        | 476 +++++++++++++++++++++++
>  tools/perf/builtin-bench.c               |   1 +
>  tools/perf/builtin-inject.c              | 199 ++++++++--
>  tools/perf/util/build-id.h               |   4 +
>  tools/perf/util/map.c                    |  17 +-
>  tools/perf/util/map.h                    |  14 +
>  9 files changed, 664 insertions(+), 55 deletions(-)
>  create mode 100644 tools/perf/bench/inject-buildid.c
> 
> -- 
> 2.28.0.1011.ga647a8990f-goog
> 

-- 

- Arnaldo