From: Giovanni Gherdovich <ggherdovich@suse.cz>
To: Ingo Molnar <mingo@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Mike Galbraith <mgalbraith@suse.de>,
Stanislaw Gruszka <sgruszka@redhat.com>,
linux-kernel@vger.kernel.org,
Mel Gorman <mgorman@techsingularity.net>
Subject: Re: [PATCH 1/1] sched/cputime: Mitigate performance regression in times()/clock_gettime()
Date: Wed, 10 Aug 2016 15:02:10 +0200 [thread overview]
Message-ID: <1470834130.1954.5.camel@suse.cz> (raw)
In-Reply-To: <20160810112641.GA30126@gmail.com>
Hello Ingo,
thank you for your reply.
Ingo Molnar <mingo@kernel.org>
> Nice detective work! I'm wondering, where do we stand if compared with a
> pre-6e998916dfe3 kernel?
The data follows. A considerable part of the performance loss is recovered;
something is still on the table.
"3.18-pre-bug" is the parent of 6e998916dfe3, i.e. 6e998916dfe3^1
"3.18-bug" is the revision 6e998916dfe3 itself.
Figures are in seconds. Percentages refer to 3.18-pre-bug, negative = worse.
times()
threads 3.18-pre-bug 3.18-bug 4.7.0-rc7 4.7.0-rc7-patched
2 2.27 ( 0.00%) 3.73 (-64.71%) 3.65 (-61.14%) 3.06 (-35.16%)
5 2.78 ( 0.00%) 3.77 (-35.56%) 3.45 (-23.98%) 3.25 (-16.79%)
8 2.79 ( 0.00%) 4.41 (-57.71%) 3.52 (-26.05%) 3.26 (-16.53%)
12 3.02 ( 0.00%) 3.56 (-17.94%) 3.29 ( -9.08%) 3.37 (-11.74%)
21 3.10 ( 0.00%) 4.61 (-48.74%) 4.07 (-31.34%) 3.90 (-25.89%)
30 3.33 ( 0.00%) 5.75 (-72.53%) 3.87 (-16.01%) 3.36 ( -0.81%)
48 2.96 ( 0.00%) 6.06 (-105.04%) 3.79 (-28.10%) 3.11 ( -5.14%)
79 2.88 ( 0.00%) 6.24 (-116.83%) 3.88 (-34.81%) 3.16 ( -9.84%)
110 2.98 ( 0.00%) 6.37 (-114.08%) 3.90 (-31.12%) 3.25 ( -9.07%)
128 3.10 ( 0.00%) 6.35 (-104.61%) 4.00 (-28.87%) 3.31 ( -6.57%)
clock_gettime()
threads 3.18-pre-bug 3.18-bug 4.7.0-rc7 4.7.0-rc7-patched
2 2.23 ( 0.00%) 3.68 (-64.56%) 3.48 (-55.48%) 3.25 (-45.41%)
5 2.83 ( 0.00%) 3.78 (-33.42%) 3.33 (-17.43%) 3.17 (-12.03%)
8 2.84 ( 0.00%) 4.31 (-52.12%) 3.37 (-18.76%) 3.22 (-13.43%)
12 3.09 ( 0.00%) 3.61 (-16.74%) 3.32 ( -7.17%) 3.36 ( -8.47%)
21 3.14 ( 0.00%) 4.63 (-47.36%) 4.01 (-27.71%) 3.92 (-24.68%)
30 3.28 ( 0.00%) 5.75 (-75.37%) 3.63 (-10.80%) 3.40 ( -3.69%)
48 3.02 ( 0.00%) 6.05 (-100.56%) 3.71 (-22.99%) 3.16 ( -4.64%)
79 2.88 ( 0.00%) 6.30 (-118.90%) 3.75 (-30.26%) 3.28 (-13.93%)
110 2.95 ( 0.00%) 6.46 (-119.00%) 3.81 (-29.24%) 3.38 (-14.69%)
128 3.05 ( 0.00%) 6.42 (-110.08%) 3.88 (-27.04%) 3.38 (-10.70%)
Regards,
Giovanni Gherdovich
next prev parent reply other threads:[~2016-08-10 18:23 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-08-05 8:21 [PATCH 0/1] " Giovanni Gherdovich
2016-08-05 8:21 ` [PATCH 1/1] " Giovanni Gherdovich
2016-08-10 11:26 ` Ingo Molnar
2016-08-10 13:02 ` Giovanni Gherdovich [this message]
2016-08-12 12:10 ` Stanislaw Gruszka
2016-08-15 7:49 ` Giovanni Gherdovich
2016-08-15 8:33 ` Mel Gorman
2016-08-15 9:19 ` Stanislaw Gruszka
2016-08-15 9:58 ` Mel Gorman
2016-08-15 10:29 ` Stanislaw Gruszka
2016-08-15 9:13 ` Wanpeng Li
2016-08-15 9:21 ` Stanislaw Gruszka
2016-08-15 9:28 ` Wanpeng Li
2016-08-10 18:00 ` [tip:sched/core] " tip-bot for Giovanni Gherdovich
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