Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 23 Mar 2003 22:06:42 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 23 Mar 2003 22:06:42 -0500 Received: from packet.digeo.com ([12.110.80.53]:64766 "EHLO packet.digeo.com") by vger.kernel.org with ESMTP id ; Sun, 23 Mar 2003 22:06:41 -0500 Date: Sun, 23 Mar 2003 19:17:44 -0800 From: Andrew Morton To: "Martin J. Bligh" Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: 2.5.65-mm4 Message-Id: <20030323191744.56537860.akpm@digeo.com> In-Reply-To: <9590000.1048475057@[10.10.2.4]> References: <20030323020646.0dfcc17b.akpm@digeo.com> <9590000.1048475057@[10.10.2.4]> X-Mailer: Sylpheed version 0.8.9 (GTK+ 1.2.10; i586-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 24 Mar 2003 03:17:30.0917 (UTC) FILETIME=[E7BD2D50:01C2F1B3] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1081 Lines: 34 "Martin J. Bligh" wrote: > > profile from SDET 64: SDET is rather irritating because a) nobody has a copy and b) we don't even know what it does. > > 82303 __down > 42835 schedule > 31323 __wake_up > 26435 .text.lock.sched > 15924 .text.lock.transaction But judging by this, it's a rebadged dbench. The profile is identical. Note that the lock_kernel() contention has been drastically reduced and we're now hitting semaphore contention. Running `dbench 32' on the quad Xeon, this patch took the context switch rate from 500/sec up to 125,000/sec. I've asked Alex to put together a patch for spinlock-based locking in the block allocator (cut-n-paste from ext2). That will fix up lock_super(), but I suspect the main problem is the lock_journal() in journal_start(). I haven't thought about that one yet. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/