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author | Joel Fernandes (Google) <joel@joelfernandes.org> | 2020-09-25 19:56:34 -0400 |
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committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2020-10-13 11:01:42 -0300 |
commit | dc000c4593a9ce119ba7db2c4d9a00f5a9daf731 (patch) | |
tree | 630fdb840999a7412f141e1e7ad3116123e5035a /tools/lib/traceevent/event-plugin.c | |
parent | 70830f974e8db9b43e61d9b223682e13e557022f (diff) | |
download | linux-stable-dc000c4593a9ce119ba7db2c4d9a00f5a9daf731.tar.gz linux-stable-dc000c4593a9ce119ba7db2c4d9a00f5a9daf731.tar.bz2 linux-stable-dc000c4593a9ce119ba7db2c4d9a00f5a9daf731.zip |
perf sched: Show start of latency as well
The 'perf sched latency' tool is really useful at showing worst-case
latencies that task encountered since wakeup. However it shows only the
end of the latency. Often times the start of a latency is interesting as
it can show what else was going on at the time to cause the latency. I
certainly myself spending a lot of time backtracking to the start of the
latency in "perf sched script" which wastes a lot of time.
This patch therefore adds a new column "Max delay start". Considering
this, also rename "Maximum delay at" to "Max delay end" as its easier to
understand.
Example of the new output:
----------------------------------------------------------------------------------------------------------------------------------
Task | Runtime ms | Switches | Avg delay ms | Max delay ms | Max delay start | Max delay end |
----------------------------------------------------------------------------------------------------------------------------------
MediaScannerSer:11936 | 651.296 ms | 67978 | avg: 0.113 ms | max: 77.250 ms | max start: 477.691360 s | max end: 477.768610 s
audio@2.0-servi:(3) | 0.000 ms | 3440 | avg: 0.034 ms | max: 72.267 ms | max start: 477.697051 s | max end: 477.769318 s
AudioOut_1D:8112 | 0.000 ms | 2588 | avg: 0.083 ms | max: 64.020 ms | max start: 477.710740 s | max end: 477.774760 s
Time-limited te:14973 | 7966.090 ms | 24807 | avg: 0.073 ms | max: 15.563 ms | max start: 477.162746 s | max end: 477.178309 s
surfaceflinger:8049 | 9.680 ms | 603 | avg: 0.063 ms | max: 13.275 ms | max start: 476.931791 s | max end: 476.945067 s
HeapTaskDaemon:(3) | 1588.830 ms | 7040 | avg: 0.065 ms | max: 6.880 ms | max start: 473.666043 s | max end: 473.672922 s
mount-passthrou:(3) | 1370.809 ms | 68904 | avg: 0.011 ms | max: 6.524 ms | max start: 478.090630 s | max end: 478.097154 s
ReferenceQueueD:(3) | 11.794 ms | 1725 | avg: 0.014 ms | max: 6.521 ms | max start: 476.119782 s | max end: 476.126303 s
writer:14077 | 18.410 ms | 1427 | avg: 0.036 ms | max: 6.131 ms | max start: 474.169675 s | max end: 474.175805 s
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20200925235634.4089867-1-joel@joelfernandes.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/lib/traceevent/event-plugin.c')
0 files changed, 0 insertions, 0 deletions