From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751281AbZHaUjZ (ORCPT ); Mon, 31 Aug 2009 16:39:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750878AbZHaUjY (ORCPT ); Mon, 31 Aug 2009 16:39:24 -0400 Received: from smtp5-g21.free.fr ([212.27.42.5]:60332 "EHLO smtp5-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750829AbZHaUjX (ORCPT ); Mon, 31 Aug 2009 16:39:23 -0400 Message-ID: <4A9C34F8.2010307@corp.free.fr> Date: Mon, 31 Aug 2009 22:39:20 +0200 From: Yohan User-Agent: Thunderbird 2.0.0.22 (Windows/20090605) MIME-Version: 1.0 To: Yohan CC: Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: VM issue causing high CPU loads References: <4A92A25A.4050608@yohan.staff.proxad.net> <20090824162155.ce323f08.akpm@linux-foundation.org> <4A96463E.5080002@corp.free.fr> In-Reply-To: <4A96463E.5080002@corp.free.fr> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Yohan wrote: > Andrew Morton wrote: >> On Mon, 24 Aug 2009 16:23:22 +0200 >> Yohan wrote: >>> Hi, >>> >>> Is someone have an idea for that : >>> >>> http://bugzilla.kernel.org/show_bug.cgi?id=14024 >>> >> Please generate a kernel profile to work out where all the CPU tie is >> being spent. Documentation/basic_profiling.txt is a starting point. >> > I post some new reports, it seems that the problem is in > rpcauth_lookup_credcache ... > > for information, this is an imap mail server that mounts ~10 netapp > over ~300 mountpoints.. I saw that : http://patchwork.kernel.org/patch/24747/ I did only: --- linux-2.6.27.21/include/linux/sunrpc/auth.h 2009-03-23 23:04:09.000000000 +0100 +++ linux-2.6.27.21/include/linux/sunrpc/auth.h 2009-05-19 16:02:35.000000000 +0200 @@ -62,8 +62,12 @@ */ - #define RPC_CREDCACHE_HASHBITS 4 + #define RPC_CREDCACHE_HASHBITS 12 And i test it in prod since sunday: i only have 36% of one core used by system versus more than 3 cores used by system in another server that did a drop_caches at morning... Yohan