Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030742AbXBOT0S (ORCPT ); Thu, 15 Feb 2007 14:26:18 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030750AbXBOT0S (ORCPT ); Thu, 15 Feb 2007 14:26:18 -0500 Received: from pfx2.jmh.fr ([194.153.89.55]:60877 "EHLO pfx2.jmh.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030742AbXBOT0R (ORCPT ); Thu, 15 Feb 2007 14:26:17 -0500 From: Eric Dumazet To: bert hubert Subject: Re: [patch 05/11] syslets: core code Date: Thu, 15 Feb 2007 20:26:08 +0100 User-Agent: KMail/1.9.5 Cc: Linus Torvalds , Evgeniy Polyakov , Ingo Molnar , Linux Kernel Mailing List , Arjan van de Ven , Christoph Hellwig , Andrew Morton , Alan Cox , Ulrich Drepper , Zach Brown , "David S. Miller" , Benjamin LaHaise , Suparna Bhattacharya , Davide Libenzi , Thomas Gleixner References: <20070213142035.GF638@elte.hu> <20070215184656.GA12897@outpost.ds9a.nl> In-Reply-To: <20070215184656.GA12897@outpost.ds9a.nl> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200702152026.08541.dada1@cosmosbay.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 923 Lines: 17 On Thursday 15 February 2007 19:46, bert hubert wrote: > Both 1 and 2 are currently limiting factors when I enter the 100kqps domain > of name serving. This doesn't mean the rest of my code is as tight as it > could be, but I spend a significant portion of time in the kernel even at > moderate (10kqps effective) loads, even though I already use epoll. A busy > PowerDNS recursor typically spends 25% to 50% of its time on 'sy' load. Well, I guess in your workload most of system overhead is because of sockets creation/destruction, UDP/IP stack work, nic driver, interrupts... I really doubt async_io could help you... Do you have some oprofile results to share with us ? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/