public inbox for kvm@vger.kernel.org
 help / color / mirror / Atom feed
From: Wanpeng Li <kernellwp@gmail.com>
To: Paolo Bonzini <pbonzini@redhat.com>,
	Avi Kivity <avi.kivity@gmail.com>, Gleb Natapov <gleb@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>, kvm list <kvm@vger.kernel.org>
Subject: Re: Seeking a KVM benchmark
Date: Mon, 17 Nov 2014 20:14:19 +0800	[thread overview]
Message-ID: <5469E69B.7050406@gmail.com> (raw)
In-Reply-To: <5469E43F.5090301@redhat.com>

Hi Paolo,
On 11/17/14, 8:04 PM, Paolo Bonzini wrote:
>
> On 17/11/2014 13:00, Wanpeng Li wrote:
>> Sorry, maybe I didn't state my question clearly. As Avi mentioned above
>> "In VMX we have VPIDs, so we only need to flush if EFER changed between
>> two invocations of the same VPID", so there is only one VPID if the
>> guest is UP, my question is if there need a TLB flush when guest's EFER
>> has been changed?
> Yes, because the meaning of the page table entries has changed.

So both VMX EFER writes and non-VMX EFER writes cause a TLB flush for UP 
guest, is there still a performance improvement in this case?

Regards,
Wanpeng Li

>
> Paolo


  reply	other threads:[~2014-11-17 12:14 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-11-07  6:27 Seeking a KVM benchmark Andy Lutomirski
2014-11-07  7:17 ` Paolo Bonzini
2014-11-07 17:59   ` Andy Lutomirski
2014-11-07 18:11     ` Andy Lutomirski
2014-11-08 12:01     ` Gleb Natapov
2014-11-08 16:00       ` Andy Lutomirski
2014-11-08 16:44         ` Andy Lutomirski
2014-11-09  8:52           ` Gleb Natapov
2014-11-09 16:36             ` Andy Lutomirski
2014-11-10 10:03               ` Paolo Bonzini
2014-11-10 10:45                 ` Gleb Natapov
2014-11-10 12:15                   ` Paolo Bonzini
2014-11-10 14:23                     ` Avi Kivity
2014-11-10 17:28                       ` Paolo Bonzini
2014-11-10 17:38                         ` Gleb Natapov
2014-11-12 11:33                           ` Paolo Bonzini
2014-11-12 15:22                             ` Gleb Natapov
2014-11-12 15:26                               ` Paolo Bonzini
2014-11-12 15:32                                 ` Gleb Natapov
2014-11-12 15:51                                   ` Paolo Bonzini
2014-11-12 16:07                                     ` Andy Lutomirski
2014-11-12 17:56                                       ` Paolo Bonzini
2014-11-17 11:17                         ` Wanpeng Li
2014-11-17 11:18                           ` Paolo Bonzini
2014-11-17 12:00                             ` Wanpeng Li
2014-11-17 12:04                               ` Paolo Bonzini
2014-11-17 12:14                                 ` Wanpeng Li [this message]
2014-11-17 12:22                                   ` Paolo Bonzini
2014-11-11 11:07                     ` Paolo Bonzini
2014-11-10 19:17                   ` Andy Lutomirski

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=5469E69B.7050406@gmail.com \
    --to=kernellwp@gmail.com \
    --cc=avi.kivity@gmail.com \
    --cc=gleb@kernel.org \
    --cc=kvm@vger.kernel.org \
    --cc=luto@amacapital.net \
    --cc=pbonzini@redhat.com \
    /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