From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261295AbVFNHQc (ORCPT ); Tue, 14 Jun 2005 03:16:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261294AbVFNHQc (ORCPT ); Tue, 14 Jun 2005 03:16:32 -0400 Received: from out01.east.net ([210.56.193.7]:4582 "EHLO out01.east.net") by vger.kernel.org with ESMTP id S261282AbVFNHQ2 (ORCPT ); Tue, 14 Jun 2005 03:16:28 -0400 Subject: 2.6 kernel series have noticeable performance regression From: yangyi Reply-To: yang.yi@bmrtech.com To: LKML Cc: China Performance Team Content-Type: text/plain Organization: bmrtech Message-Id: <1118733263.10339.1553.camel@montavista2> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 Date: Tue, 14 Jun 2005 15:14:24 +0800 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, All I did a performance regression test for all the 2.6 kernel series on two x86 platforms in last two weeks and found that some version kernels do have noticeable performance regression, some performance indices have about 20 to 30 percent regression, even several indices have over 30 percent fall. For example, on Toshiba tecra8000 laptop: for 4-bytes packet, network throughput of 2.6.11 is just about 57.5 percent of 2.6.0, for pipe bandwidth, the value of 2.6.11 is just about 68 percent of that value of 2.6.0, for mmap latency, the value of 2.6.11 is about 1.8 times as long as 2.6.0. On supermicro-6012-p6, for 64-bytes small packet, network throughput of 2.6.11 is about 66.72 percent of 2.6.0, for 0K-size 2 processes context switch time, 2.6.11 is 31.8 percent bigger than 2.6.0, for pipe latency, 2.6.10 is 35.85 percent bigger than 2.6.3. So, I think that it is very very necessary to find the problems and fix them ASAP. The following articles give out all the test results, the article "2.6 kernel series have noticeable performance regression, part 1" gives out the test results on SuperMicro-6012-p6, the article "2.6 kernel series have noticeable performance regression, part 2" gives out the test results on Toshiba tecra8000 laptop.