Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751090AbWB1WTM (ORCPT ); Tue, 28 Feb 2006 17:19:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751092AbWB1WTM (ORCPT ); Tue, 28 Feb 2006 17:19:12 -0500 Received: from mail.atl.external.lmco.com ([192.35.37.50]:13260 "EHLO enterprise.atl.lmco.com") by vger.kernel.org with ESMTP id S1751090AbWB1WTM (ORCPT ); Tue, 28 Feb 2006 17:19:12 -0500 Message-ID: <4404CC58.2020805@atl.lmco.com> Date: Tue, 28 Feb 2006 17:19:04 -0500 From: Gautam H Thaker Organization: Lockheed Martin -- Advanced Technology Laboratories User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.12) Gecko/20050920 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Matt Mackall Cc: Gautam H Thaker , linux-kernel@vger.kernel.org, Ingo Molnar Subject: Re: ~5x greater CPU load for a networked application when using 2.6.15-rt15-smp vs. 2.6.12-1.1390_FC4 References: <43FE134C.6070600@atl.lmco.com> <20060228192738.GO4650@waste.org> In-Reply-To: <20060228192738.GO4650@waste.org> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1155 Lines: 35 Matt Mackall wrote: > On Thu, Feb 23, 2006 at 02:55:56PM -0500, Gautam H Thaker wrote: > >>The real-time patches at the URL below do a great job of endowing Linux with >>real-time capabilities. >> >>http://people.redhat.com/mingo/realtime-preempt/ >> >>It has been documented before (and accepted) that this patch turns Linux into >>a RT kernel but considerably slows down the code paths, esp. thru the I/O >>subsystem. I want to provide some additional measurements and seek opinions >>of if it might ever be possible to improve on this situation. > > > Are you using the SLAB or SLOB allocator in the -rt kernel? lake> grep SL config.2.6.15-rt15-smp CONFIG_SEMAPHORE_SLEEPERS=y CONFIG_SLAB=y # CONFIG_SLOB is not set -- Gautam H. Thaker Distributed Processing Lab; Lockheed Martin Adv. Tech. Labs 3 Executive Campus; Cherry Hill, NJ 08002 856-792-9754, fax 856-792-9925 email: gthaker@atl.lmco.com - 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/