public inbox for kvm@vger.kernel.org
 help / color / mirror / Atom feed
From: Chegu Vinod <chegu_vinod@hp.com>
To: Jiannan Ouyang <ouyang@cs.pitt.edu>
Cc: Peter Zijlstra <peterz@infradead.org>,
	Rik van Riel <riel@redhat.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>,
	Avi Kivity <avi.kivity@gmail.com>, Gleb Natapov <gleb@redhat.com>,
	Ingo Molnar <mingo@redhat.com>,
	Marcelo Tosatti <mtosatti@redhat.com>,
	Srikar <srikar@linux.vnet.ibm.com>,
	"H. Peter Anvin" <hpa@zytor.com>,
	"Nikunj A. Dadhania" <nikunj@linux.vnet.ibm.com>,
	KVM <kvm@vger.kernel.org>, Thomas Gleixner <tglx@linutronix.de>,
	"Andrew M. Theurer" <habanero@linux.vnet.ibm.com>,
	Srivatsa Vaddagiri <srivatsa.vaddagiri@gmail.com>,
	Andrew Jones <drjones@redhat.com>, Karen Noel <knoel@redhat.com>
Subject: Re: Preemptable Ticket Spinlock
Date: Mon, 22 Apr 2013 13:54:37 -0700	[thread overview]
Message-ID: <5175A38D.4070002@hp.com> (raw)
In-Reply-To: <CAJocwcf2=+oWmn3EvNnCA5U81LPA=Ue8=RNYDJb_J6wNYmgNMQ@mail.gmail.com>

On 4/22/2013 1:50 PM, Jiannan Ouyang wrote:
> On Mon, Apr 22, 2013 at 4:44 PM, Peter Zijlstra <peterz@infradead.org> wrote:
>> On Mon, 2013-04-22 at 16:32 -0400, Rik van Riel wrote:
>>> IIRC one of the reasons was that the performance improvement wasn't
>>> as obvious.  Rescheduling VCPUs takes a fair amount of time, quite
>>> probably more than the typical hold time of a spinlock.
>> IIRC it would spin for a while before blocking..
>>
>> /me goes re-read some of that thread...
>>
>> Ah, its because PLE is curing most of it.. !PLE it had huge gains but
>> apparently nobody cares about !PLE hardware anymore :-)
>>
> For now, I don't know how good it can work with PLE. But I think it
> should save the time of VMEXIT on PLE machine.
> .
>
Thanks for sharing your patch. 'am waiting for your v2 patch(es) and 
then let you any review feedback. Hoping to verify your changes on a 
large box (PLE enabled) and get back to you with some data...

Thanks
Vinod

  reply	other threads:[~2013-04-22 20:54 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <CAJocwccu5QQyuKRvgNyPSFz2K_rzCW419W9-XdSUYOL7+KqQKg@mail.gmail.com>
2013-04-21 21:12 ` Preemptable Ticket Spinlock Rik van Riel
2013-04-21 23:07   ` Jiannan Ouyang
2013-04-22  5:59     ` Raghavendra K T
2013-04-22 11:51   ` Peter Zijlstra
2013-04-22 12:52     ` Rik van Riel
2013-04-22 19:49       ` Peter Zijlstra
2013-04-22 19:56         ` Rik van Riel
2013-04-22 20:05           ` Jiannan Ouyang
2013-04-22 20:08           ` Peter Zijlstra
2013-04-22 20:32             ` Rik van Riel
2013-04-22 20:44               ` Peter Zijlstra
2013-04-22 20:48                 ` Peter Zijlstra
2013-04-22 20:50                   ` Rik van Riel
2013-04-22 20:50                 ` Jiannan Ouyang
2013-04-22 20:54                   ` Chegu Vinod [this message]
2013-04-22 20:46             ` Jiannan Ouyang
2013-04-22 20:49               ` Rik van Riel
2013-04-22 21:01                 ` Peter Zijlstra
2013-04-23  5:03                   ` Raghavendra K T
2013-04-22 20:55               ` Peter Zijlstra
2013-04-22 21:31                 ` Jiannan Ouyang
2013-04-22 23:08                 ` Rik van Riel
2013-04-23  5:57                   ` Gleb Natapov
2013-04-23  1:42         ` Raghavendra K T
2013-05-30 11:56           ` Raghavendra K T
2013-05-30 20:14             ` Thomas Gleixner
2013-04-22 21:56   ` Andi Kleen
2013-04-22 23:13     ` Rik van Riel
2013-04-22  5:58 ` Raghavendra K T
2013-04-22 16:42   ` Jiannan Ouyang
2013-04-23  1:54     ` Raghavendra K T
2013-04-26 20:10 ` Andrew Theurer

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=5175A38D.4070002@hp.com \
    --to=chegu_vinod@hp.com \
    --cc=avi.kivity@gmail.com \
    --cc=drjones@redhat.com \
    --cc=gleb@redhat.com \
    --cc=habanero@linux.vnet.ibm.com \
    --cc=hpa@zytor.com \
    --cc=knoel@redhat.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=mtosatti@redhat.com \
    --cc=nikunj@linux.vnet.ibm.com \
    --cc=ouyang@cs.pitt.edu \
    --cc=peterz@infradead.org \
    --cc=raghavendra.kt@linux.vnet.ibm.com \
    --cc=riel@redhat.com \
    --cc=srikar@linux.vnet.ibm.com \
    --cc=srivatsa.vaddagiri@gmail.com \
    --cc=tglx@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox