From: Mike Galbraith <bitbucket@online.de>
To: Peter Zijlstra <peterz@infradead.org>
Cc: LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>
Subject: Re: sched: context tracking demolishes pipe-test
Date: Mon, 01 Jul 2013 08:07:55 +0200 [thread overview]
Message-ID: <1372658875.7678.17.camel@marge.simpson.net> (raw)
In-Reply-To: <20130630212940.GK6626@twins.programming.kicks-ass.net>
On Sun, 2013-06-30 at 23:29 +0200, Peter Zijlstra wrote:
> Yeah, who'd have thought that putting stuff in the syscall path would've
> made syscalls more expensive ;-)
(careful, you'll injure my innocence, Santa and the Tooth Fairy exist!)
> But yeah, that's a _lot_ more expensive.. I'd not be surprised if more
> people would find that objectionable.
Distros may want some hot patching or _something_ before doing the usual
new=turn-it-on thing. Per trusty (spelled with 'c') old Q6600, the cost
is pretty darn high.
-regress is my ~light regression testing config, carried forward from
3.6.32...master across all intervening trees.
-regressx is plus CONFIG_RCU_USER_QS=y CONFIG_CONTEXT_TRACKING_FORCE=y
-regressxx is plus full dynticks
taskset -c 3 pipe-test 1
2.6.32-regress 654.5 Khz 1.000
3.10.0-regress 652.1 Khz .996 1.000
3.10.0-regressx 476.8 Khz .728 .731
3.10.0-regressxx 275.6 Khz .421 .422
tbench
2.6.32-regress 327.502 MB/sec 1.000
3.10.0-regress 319.621 MB/sec .975 1.000
3.10.0-regressx 292.894 MB/sec .894 .916
3.10.0-regressxx 243.738 MB/sec .744 .762
netperf TCP_RR
2.6.32-regress 104041.84 Trans/sec 1.000
3.10.0-regress 94961.34 Trans/sec .912 1.000
3.10.0-regressx 82383.33 Trans/sec .791 .867
3.10.0-regressxx 61527.59 Trans/sec .591 .647
next prev parent reply other threads:[~2013-07-01 6:08 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-06-30 7:57 sched: context tracking demolishes pipe-test Mike Galbraith
2013-06-30 21:29 ` Peter Zijlstra
2013-07-01 6:07 ` Mike Galbraith [this message]
2013-07-01 8:06 ` Peter Zijlstra
2013-07-01 9:12 ` Mike Galbraith
2013-07-01 9:20 ` Mike Galbraith
2013-07-02 4:03 ` Mike Galbraith
2013-07-02 7:19 ` Mike Galbraith
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