From: Rik van Riel <riel@redhat.com>
To: "Alex,Shi" <alex.shi@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"mingo@elte.hu" <mingo@elte.hu>,
"Chen, Tim C" <tim.c.chen@intel.com>,
"Li, Shaohua" <shaohua.li@intel.com>
Subject: Re: [PATCH] sched: recover sched_yield task running time increase
Date: Thu, 07 Apr 2011 02:13:03 -0400 [thread overview]
Message-ID: <4D9D55EF.3090606@redhat.com> (raw)
In-Reply-To: <1302145733.15889.7472.camel@debian>
On 04/06/2011 11:08 PM, Alex,Shi wrote:
> On Wed, 2011-04-06 at 16:04 +0800, Peter Zijlstra wrote:
>> On Wed, 2011-04-06 at 06:33 +0800, Alex Shi wrote:
>> You do know that any app that relies on sched_yield behaviour is more
>> than broken? Using sched_yield() for anything other than SCHED_FIFO
>> tasks is well outside spec.
>>
>> Furthermore, apparently you used sysctl_sched_compat_yield, which was
>> bound to disappear some time, since with the default settings the yield
>> semantics didn't actually change.
>
> Yes, I used sched_compat_yield, otherwise volano will become extremely
> slow in my single machine testing. We may reconsider our testing
> setting.
With what JVM is this happening?
Surely not every JVM uses user space spinlocks and
yield, when we have futexes available?
next prev parent reply other threads:[~2011-04-07 6:09 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-04-05 22:33 [PATCH] sched: recover sched_yield task running time increase Alex Shi
2011-04-06 5:07 ` Rik van Riel
2011-04-06 6:15 ` Alex,Shi
2011-04-06 7:01 ` Mike Galbraith
2011-04-06 13:28 ` Shi, Alex
2011-04-07 2:44 ` Mike Galbraith
2011-04-06 8:04 ` Peter Zijlstra
2011-04-06 14:42 ` Rik van Riel
2011-04-06 15:25 ` Peter Zijlstra
2011-04-07 3:08 ` Alex,Shi
2011-04-07 6:13 ` Rik van Riel [this message]
2011-04-07 6:43 ` Alex,Shi
2011-04-07 8:52 ` Ingo Molnar
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