From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takuya Yoshikawa Subject: Re: [PATCH v2 6/8] kvm tools: Add rwlock wrapper Date: Mon, 30 May 2011 23:16:45 +0900 Message-ID: <20110530231645.3b1ef4c9.takuya.yoshikawa@gmail.com> References: <1306748069.14564.52.camel@lappy> <1306748796.14564.62.camel@lappy> <20110530095451.GB8461@elte.hu> <20110530201110.f3bf20b5.yoshikawa.takuya@oss.ntt.co.jp> <1306753954.14564.92.camel@lappy> <20110530202646.eff0ea28.yoshikawa.takuya@oss.ntt.co.jp> <4DE381DB.8040804@redhat.com> <20110530114949.GD22324@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Avi Kivity , Takuya Yoshikawa , Sasha Levin , Pekka Enberg , kvm@vger.kernel.org, asias.hejun@gmail.com, gorcunov@gmail.com, prasadjoshi124@gmail.com, "Paul E. McKenney" To: Ingo Molnar Return-path: Received: from mail-pv0-f174.google.com ([74.125.83.174]:42204 "EHLO mail-pv0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751689Ab1E3OQv (ORCPT ); Mon, 30 May 2011 10:16:51 -0400 Received: by pvg12 with SMTP id 12so1629636pvg.19 for ; Mon, 30 May 2011 07:16:50 -0700 (PDT) In-Reply-To: <20110530114949.GD22324@elte.hu> Sender: kvm-owner@vger.kernel.org List-ID: On Mon, 30 May 2011 13:49:49 +0200 Ingo Molnar wrote: > > Note, with cpu overcommit the results are going to be bad. > > And that is good: if pushed hard enough it will trigger exciting (or > obscure) bugs in the guest kernel much faster than if there's no > overcommit, so it's rather useful for testing. (We made that > surprising experience with -rt.) > > Also, such simulation would be very obviously useful if you get > bugreports about 1024 or 4096 CPUs, like i do sometimes! :-) [*] > Yes, that is exactly what I wanted to see. 16 core server is the best I can use now, and usually I only use 4 core desktop! Takuya