From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751031AbVHSDTj (ORCPT ); Thu, 18 Aug 2005 23:19:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751033AbVHSDTi (ORCPT ); Thu, 18 Aug 2005 23:19:38 -0400 Received: from ns1.suse.de ([195.135.220.2]:47043 "EHLO mx1.suse.de") by vger.kernel.org with ESMTP id S1751031AbVHSDTi (ORCPT ); Thu, 18 Aug 2005 23:19:38 -0400 To: Bernardo Innocenti Cc: linux-kernel@vger.kernel.org, nickpiggin@yahoo.com.au Subject: Re: sched_yield() makes OpenLDAP slow References: <4303DB48.8010902@develer.com.suse.lists.linux.kernel> <20050818010703.GA13127@nineveh.rivenstone.net.suse.lists.linux.kernel> <4303F967.6000404@yahoo.com.au.suse.lists.linux.kernel> <43054D9A.7090509@develer.com.suse.lists.linux.kernel> From: Andi Kleen Date: 19 Aug 2005 05:19:37 +0200 In-Reply-To: <43054D9A.7090509@develer.com.suse.lists.linux.kernel> Message-ID: User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Bernardo Innocenti writes: It's really more a feature than a bug that it breaks so easily because they should be really using futexes instead, which have much better behaviour than any sched_yield ever could (they will directly wake up another process waiting for the lock and avoid the thundering herd for contended locks) -Andi