From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Glauber Costa <glommer@parallels.com>
Cc: linux-kernel@vger.kernel.org, xemul@parallels.com,
paul@paulmenage.org, lizf@cn.fujitsu.com, daniel.lezcano@free.fr,
mingo@elte.hu, jbottomley@parallels.com
Subject: Re: [PATCH 0/9] Per-cgroup /proc/stat
Date: Thu, 15 Sep 2011 10:53:09 +0200 [thread overview]
Message-ID: <1316076789.3045.4.camel@twins> (raw)
In-Reply-To: <4E710C93.40609@parallels.com>
On Wed, 2011-09-14 at 17:20 -0300, Glauber Costa wrote:
> Answering just a single point here, if you look closely, it does not
> duplicate anything from cpuacct. What it does, is to divide it in more
> fine grained groups than just user/system. But it is not even called
> more than it already used to be. Also, I change the counters to per-cpu
> variables instead of percpu counters (so we can access per-cpu data). If
> there is any perf. change wrt the current code, it comes from that, and
> since percpu variables are cheaper to update (and summing up is much
> less frequent), it will end up even cheaper.
I just saw the word statistics and 234 lines added to sched.c and went
mental ;-)
> The steal time feature is really trivial once it is in place.
>
> About your point of the context switch cost, how would you feel if we
> optimized it out using static_branch() like it was done for kvm steal time?
Both pjt and me tried, but its hard, part of the problem is also data
structure bloat.
next prev parent reply other threads:[~2011-09-15 8:53 UTC|newest]
Thread overview: 58+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-14 20:04 [PATCH 0/9] Per-cgroup /proc/stat Glauber Costa
2011-09-14 20:04 ` [PATCH 1/9] Remove parent field in cpuacct cgroup Glauber Costa
2011-09-19 16:03 ` Peter Zijlstra
2011-09-19 16:09 ` Glauber Costa
2011-09-19 16:19 ` Peter Zijlstra
2011-09-19 16:30 ` Glauber Costa
2011-09-19 16:39 ` Peter Zijlstra
2011-09-19 16:41 ` Glauber Costa
2011-09-19 18:40 ` Peter Zijlstra
2011-09-20 17:29 ` Srivatsa Vaddagiri
2011-09-22 15:11 ` Balbir Singh
2011-09-22 15:17 ` Peter Zijlstra
2011-09-23 8:09 ` Balbir Singh
2011-09-23 14:35 ` Peter Zijlstra
2011-09-23 15:45 ` Glauber Costa
2011-09-19 18:35 ` Peter Zijlstra
2011-09-19 18:38 ` Glauber Costa
2011-09-19 18:44 ` Peter Zijlstra
2011-09-19 19:14 ` Glauber Costa
2011-09-19 19:18 ` Peter Zijlstra
2011-09-19 19:19 ` Glauber Costa
2011-09-14 20:04 ` [PATCH 2/9] Make cpuacct fields per cpu variables Glauber Costa
2011-09-19 16:10 ` Peter Zijlstra
2011-09-14 20:04 ` [PATCH 3/9] Include nice values in cpuacct Glauber Costa
2011-09-19 16:19 ` Peter Zijlstra
2011-09-19 16:26 ` Glauber Costa
2011-09-19 18:36 ` Peter Zijlstra
2011-09-19 18:37 ` Glauber Costa
2011-09-14 20:04 ` [PATCH 4/9] Include irq and softirq fields " Glauber Costa
2011-09-19 18:38 ` Peter Zijlstra
2011-09-19 18:40 ` Glauber Costa
2011-09-14 20:04 ` [PATCH 5/9] Include guest " Glauber Costa
2011-09-14 20:04 ` [PATCH 6/9] Include idle and iowait " Glauber Costa
2011-09-20 9:21 ` Peter Zijlstra
2011-09-20 12:36 ` Glauber Costa
2011-09-20 12:58 ` Peter Zijlstra
2011-09-20 12:58 ` Glauber Costa
2011-09-20 13:05 ` Peter Zijlstra
2011-09-20 13:29 ` Glauber Costa
2011-09-14 20:04 ` [PATCH 7/9] Create cpuacct.proc.stat file Glauber Costa
2011-09-20 9:22 ` Peter Zijlstra
2011-09-20 12:22 ` Glauber Costa
2011-09-14 20:04 ` [PATCH 8/9] per-cgroup boot time Glauber Costa
2011-09-20 9:25 ` Peter Zijlstra
2011-09-20 12:37 ` Glauber Costa
2011-09-20 13:04 ` Peter Zijlstra
2011-09-20 13:06 ` Glauber Costa
2011-09-20 13:31 ` Peter Zijlstra
2011-09-14 20:04 ` [PATCH 9/9] Report steal time for cgroup Glauber Costa
2011-09-20 9:29 ` Peter Zijlstra
2011-09-14 20:13 ` [PATCH 0/9] Per-cgroup /proc/stat Peter Zijlstra
2011-09-14 20:20 ` Glauber Costa
2011-09-15 8:53 ` Peter Zijlstra [this message]
2011-09-14 20:23 ` Andi Kleen
2011-09-15 8:56 ` Peter Zijlstra
2011-09-19 23:07 ` Paul Turner
2011-09-20 8:33 ` Peter Zijlstra
2011-09-20 21:37 ` Glauber Costa
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