From: Avi Kivity <avi@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Srivatsa Vaddagiri <vatsa.ml@gmail.com>,
"Zhang, Xiantao" <xiantao.zhang@intel.com>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
Marcelo Tosatti <mtosatti@redhat.com>,
"Yang, Xiaowei" <xiaowei.yang@intel.com>,
"Dong, Eddie" <eddie.dong@intel.com>,
"Li, Xin" <xin.li@intel.com>, Ingo Molnar <mingo@elte.hu>,
Mike Galbraith <efault@gmx.de>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
vatsa@linux.vnet.ibm.com
Subject: Re: VM performance issue in KVM guests.
Date: Sat, 17 Apr 2010 22:04:38 +0300 [thread overview]
Message-ID: <4BCA0646.1000603@redhat.com> (raw)
In-Reply-To: <1271338398.1674.13.camel@laptop>
On 04/15/2010 04:33 PM, Peter Zijlstra wrote:
> On Thu, 2010-04-15 at 11:18 +0300, Avi Kivity wrote:
>
>> Certainly that has even greater potential for Linux guests. Note that
>> we spin on mutexes now, so we need to prevent preemption while the lock
>> owner is running.
>>
> either that, or disable spinning on (para) virt kernels.
What would you do instead?
Note we can't disable spinning on Windows or pre 2.6.36 kernels.
> Para virt
> kernels could possibly extend the thing by also checking to see if the
> owner's vcpu is running.
>
Certainly that's worth doing.
--
Do not meddle in the internals of kernels, for they are subtle and quick to panic.
prev parent reply other threads:[~2010-04-17 19:05 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <EB8593BCECAB3D40A8248BE0B6400A3846903F4C@shzsmsx502.ccr.corp.intel.com>
2010-04-10 19:27 ` VM performance issue in KVM guests Avi Kivity
2010-04-12 2:04 ` Zhang, Xiantao
2010-04-12 6:40 ` Avi Kivity
2010-04-13 0:50 ` Zhang, Xiantao
2010-04-13 6:46 ` Avi Kivity
2010-04-14 3:24 ` Zhang, Xiantao
2010-04-14 8:14 ` Avi Kivity
2010-04-16 2:27 ` Zhang, Xiantao
2010-04-17 19:02 ` Avi Kivity
[not found] ` <p2o2eae271004142158xaa5da968ueff0c2afe6894f9d@mail.gmail.com>
2010-04-15 8:18 ` Avi Kivity
2010-04-15 13:33 ` Peter Zijlstra
2010-04-15 16:43 ` Srivatsa Vaddagiri
2010-04-16 10:40 ` Peter Zijlstra
2010-04-19 1:32 ` Zhang, Xiantao
2010-04-17 19:04 ` Avi Kivity [this message]
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