From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752045AbWCFTvu (ORCPT ); Mon, 6 Mar 2006 14:51:50 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750715AbWCFTvu (ORCPT ); Mon, 6 Mar 2006 14:51:50 -0500 Received: from rgminet01.oracle.com ([148.87.113.118]:49469 "EHLO rgminet01.oracle.com") by vger.kernel.org with ESMTP id S1752045AbWCFTvt (ORCPT ); Mon, 6 Mar 2006 14:51:49 -0500 Date: Mon, 6 Mar 2006 11:51:35 -0800 From: Mark Fasheh To: Daniel Phillips Cc: Andrew Morton , linux-kernel@vger.kernel.org, ocfs2-devel@oss.oracle.com Subject: Re: [Ocfs2-devel] Ocfs2 performance bugs of doom Message-ID: <20060306195135.GB27280@ca-server1.us.oracle.com> Reply-To: Mark Fasheh References: <4408C2E8.4010600@google.com> <20060303233617.51718c8e.akpm@osdl.org> <440B9035.1070404@google.com> <20060306025800.GA27280@ca-server1.us.oracle.com> <440BC1C6.1000606@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <440BC1C6.1000606@google.com> Organization: Oracle Corporation User-Agent: Mutt/1.5.11 X-Brightmail-Tracker: AAAAAQAAAAI= X-Whitelist: TRUE Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Mar 05, 2006 at 08:59:50PM -0800, Daniel Phillips wrote: > So that hack apparently improves the bucket distribution quite a bit, but > look, the bad old linear systime creep is still very obvious. For that > there is no substitute for lots of buckets. Yes, I think the way to go right now is to allocate an array of pages and index into that. We can make the array size a mount option so that the default can be something reasonable ;) > Speaking of that, the qstr is so far away from the list.next pointer that > you're most probably getting an extra cache line load there too. Just move > the qstr up next to the hash list. Ahh, good catch. > Notice, those wildly gyrating real times are still manifesting. Seen > them over there? Yes - times from a test run are below. Real User Sys 14.35 3.82 11.99 16.75 3.62 13.90 32.12 4.06 15.81 18.94 3.99 16.69 35.18 3.96 15.80 18.66 3.89 16.44 52.09 4.24 16.66 21.25 3.85 17.09 19.73 4.00 17.20 35.40 3.88 16.60 So this definitely reproduces elsewhere. --Mark -- Mark Fasheh Senior Software Developer, Oracle mark.fasheh@oracle.com