[PATCHSET v3 0/6] perf inject: Speed build-id injection

From: Namhyung Kim
Date: Mon Sep 28 2020 - 03:53:01 EST


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: 23.885 msec (+- 0.114 msec)
Average time per event: 2.342 usec (+- 0.011 usec)
Average memory usage: 7864 KB (+- 10 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: 18.182 msec (+- 0.126 msec)
Average time per event: 1.783 usec (+- 0.012 usec)
Average memory usage: 7334 KB (+- 6 KB)
Average build-id-all injection took: 17.520 msec (+- 0.046 msec)
Average time per event: 1.718 usec (+- 0.005 usec)
Average memory usage: 7418 KB (+- 2 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 fixed a bug in the benchmark code not to read all the
required bytes and return early. With that, sadly, some speedup in
the build-id-all injection was gone, but it's still slightly faster
while uses more memory.

In addition, I dropped the last patch for now which changes build-id
handling when -b option is not used. As this can impact build-id-all
performance, I'll think about it more and come up with something later.


This code is available at 'perf/inject-speedup-v3' branch on

git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git


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

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2.28.0.681.g6f77f65b4e-goog