From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753525Ab1LLRWt (ORCPT ); Mon, 12 Dec 2011 12:22:49 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:37856 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753227Ab1LLRWp (ORCPT ); Mon, 12 Dec 2011 12:22:45 -0500 Date: Mon, 12 Dec 2011 18:20:59 +0100 From: Ingo Molnar To: Pekka Enberg Cc: Thomas Gleixner , LKML , Sasha Levin Subject: Re: [patch 0/3] kvm tool: Serial emulation overhaul Message-ID: <20111212172059.GC23870@elte.hu> References: <20111210132220.083204833@linutronix.de> <20111211103047.GA19299@elte.hu> <20111211155347.GA1297@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=AWL,BAYES_00 autolearn=no SpamAssassin version=3.3.1 -2.0 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] 0.0 AWL AWL: From: address is in the auto white-list Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Pekka Enberg wrote: > On Sun, Dec 11, 2011 at 5:53 PM, Ingo Molnar wrote: > > Okay, but look at it from another angle: the top output i > > generate is about 300k characters. 5000 msecs to execute it > > means 16 usecs overhead per character - or about 50k cycles - on > > a top of the class x86 CPU. > > I'm seeing 1.5 usecs per character for this little benchmark: Interesting - what do you see with the top -b measurement i posted - can you see similar slowdowns? Thanks, Ingo