From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262649AbTKDWT3 (ORCPT ); Tue, 4 Nov 2003 17:19:29 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262071AbTKDWT3 (ORCPT ); Tue, 4 Nov 2003 17:19:29 -0500 Received: from 209-166-240-202.cust.walrus.com ([209.166.240.202]:25579 "EHLO ti3.telemetry-investments.com") by vger.kernel.org with ESMTP id S262649AbTKDWT0 (ORCPT ); Tue, 4 Nov 2003 17:19:26 -0500 Date: Tue, 4 Nov 2003 17:19:04 -0500 From: "Bill Rugolsky Jr." To: Linus Torvalds Cc: Paul Venezia , Kernel Mailing List , Ulrich Drepper Subject: Re: ext3 performance inconsistencies, 2.4/2.6 Message-ID: <20031104221904.GE30612@ti19.telemetry-investments.com> Reply-To: "Bill Rugolsky Jr." Mail-Followup-To: "Bill Rugolsky Jr." , Linus Torvalds , Paul Venezia , Kernel Mailing List , Ulrich Drepper References: <20031104212813.GC30612@ti19.telemetry-investments.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 04, 2003 at 01:40:51PM -0800, Linus Torvalds wrote: > On Tue, 4 Nov 2003, Bill Rugolsky Jr. wrote: > > > > Well, I'm too lazy to wait for a long test, but with a mere > > 100MB file, on 1GHz P3: > > > > Version 1.03 ------Sequential Output------ --Sequential Input- --Random- > > -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks-- > > NPTL 100M 7735 99 127068 98 63048 84 7890 98 +++++ +++ +++++ +++ > > LinuxThreads 100M 11000 99 127928 97 59075 84 11290 98 +++++ +++ +++++ +++ > > > > So something is amiss. > > Ok, so NPTL locking (even in the absense of any threads and thus any > contention) seems to be noticeably higher-overhead than the old > LinuxThreads. > > 90% of the overhead of a putc()/getc() implementation these days is likely > just locking. Even so, this implies that NPTL locking is about twice as > expensive as the old LinuxThreads one. On Fedora 0.95, Pentium M 1.6GHz, 2.4.22-1.2115.nptl, glibc-2.3.2-10, (NPTL 0.60), I get: Version 1.03 ------Sequential Output------ --Sequential Input- --Random- -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks-- Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP NPTL 100M 13070 100 +++++ +++ 14141 4 13099 100 +++++ +++ +++++ +++ LinuxThreads 100M 25957 100 +++++ +++ 20037 5 26777 99 +++++ +++ +++++ +++ Ugh, still there. Bill Rugolsky