From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262707AbTKEHIg (ORCPT ); Wed, 5 Nov 2003 02:08:36 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262747AbTKEHIg (ORCPT ); Wed, 5 Nov 2003 02:08:36 -0500 Received: from pix-525-pool.redhat.com ([66.187.233.200]:47324 "EHLO devserv.devel.redhat.com") by vger.kernel.org with ESMTP id S262707AbTKEHIf (ORCPT ); Wed, 5 Nov 2003 02:08:35 -0500 Date: Wed, 5 Nov 2003 02:08:32 -0500 From: Jakub Jelinek To: jlnance@unity.ncsu.edu Cc: Ulrich Drepper , linux-kernel@vger.kernel.org Subject: Re: ext3 performance inconsistencies, 2.4/2.6 Message-ID: <20031105020832.V2097@devserv.devel.redhat.com> Reply-To: Jakub Jelinek References: <3FA83ACC.5060700@redhat.com> <20031105005816.GA5971@ncsu.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <20031105005816.GA5971@ncsu.edu>; from jlnance@unity.ncsu.edu on Tue, Nov 04, 2003 at 07:58:16PM -0500 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 04, 2003 at 07:58:16PM -0500, jlnance@unity.ncsu.edu wrote: > On Tue, Nov 04, 2003 at 03:48:28PM -0800, Ulrich Drepper wrote: > > > > The first is the old nptl code, the second LinuxThreads, the third the > > current nptl code. > > By current, do you mean what is in Fedora, or you personal development copy? Ulrich meant glibc CVS HEAD. For some reason, stdio locking was not using the jump around lock prefix variant of locking: __asm __volatile ("cmpl $0, %%gs:%P6\n\t" \ "je,pt 0f\n\t" \ "lock\n" \ "0:\tcmpxchgl %1, %2\n\t" \ "jnz _L_mutex_lock_%=\n\t" \ ".subsection 1\m\t" ... but one without the first 2 insns, so there were 2 instructions with lock prefix in putc and similar functions even when only one thread was running. Jakub