Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030217AbWAXH6G (ORCPT ); Tue, 24 Jan 2006 02:58:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030218AbWAXH6G (ORCPT ); Tue, 24 Jan 2006 02:58:06 -0500 Received: from mustang.oldcity.dca.net ([216.158.38.3]:5866 "HELO mustang.oldcity.dca.net") by vger.kernel.org with SMTP id S1030217AbWAXH6F (ORCPT ); Tue, 24 Jan 2006 02:58:05 -0500 Subject: Re: RCU latency regression in 2.6.16-rc1 From: Lee Revell To: Ingo Molnar Cc: linux-kernel , Linus Torvalds , "Paul E. McKenney" In-Reply-To: <20060124075640.GA24806@elte.hu> References: <1138089139.2771.78.camel@mindpipe> <20060124075640.GA24806@elte.hu> Content-Type: text/plain Date: Tue, 24 Jan 2006 02:58:02 -0500 Message-Id: <1138089483.2771.81.camel@mindpipe> Mime-Version: 1.0 X-Mailer: Evolution 2.5.4 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 737 Lines: 24 On Tue, 2006-01-24 at 08:56 +0100, Ingo Molnar wrote: > * Lee Revell wrote: > > > I ported the latency tracer to 2.6.16 and got this 13ms latency within > > a few hours. This is a regression from 2.6.15. > > > > It appears that RCU can invoke ipv4_dst_destroy thousands of times in > > a single batch. > > could you try the PREEMPT_RCU patch below? > Sure. If it works do you see this making it in 2.6.16? Otherwise we still would have a regression... Lee - 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/