From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756259AbXLST2q (ORCPT ); Wed, 19 Dec 2007 14:28:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753318AbXLST2j (ORCPT ); Wed, 19 Dec 2007 14:28:39 -0500 Received: from pentafluge.infradead.org ([213.146.154.40]:39121 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753223AbXLST2i (ORCPT ); Wed, 19 Dec 2007 14:28:38 -0500 Subject: Re: [patch 02/20] make the inode i_mmap_lock a reader/writer lock From: Peter Zijlstra To: Lee Schermerhorn Cc: Rik van Riel , Nick Piggin , linux-mm@kvack.org, linux-kernel@vger.kernel.org In-Reply-To: <1198083218.5333.48.camel@localhost> References: <20071218211539.250334036@redhat.com> <20071218211548.784184591@redhat.com> <200712191148.06506.nickpiggin@yahoo.com.au> <1198079529.5333.12.camel@localhost> <20071219113107.5301f9f0@cuia.boston.redhat.com> <1198083218.5333.48.camel@localhost> Content-Type: text/plain Date: Wed, 19 Dec 2007 20:28:23 +0100 Message-Id: <1198092503.6484.21.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.12.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2007-12-19 at 11:53 -0500, Lee Schermerhorn wrote: > On Wed, 2007-12-19 at 11:31 -0500, Rik van Riel wrote: > > On Wed, 19 Dec 2007 10:52:09 -0500 > > Lee Schermerhorn wrote: > > > > > I keep these patches up to date for testing. I don't have conclusive > > > evidence whether they alleviate or exacerbate the problem nor by how > > > much. > > > > When the queued locking from Ingo's x86 tree hits mainline, > > I suspect that spinlocks may end up behaving a lot nicer. > > That would be worth testing with our problematic workloads... > > > > > Should I drop the rwlock patches from my tree for now and > > focus on just the page reclaim stuff? > > That's fine with me. They're out there is anyone is interested. I'll > keep them up to date in my tree [and hope they don't conflict with split > lru and noreclaim patches too much] for occasional testing. Of course, someone would need to implement ticket locks for ia64 - preferably without the 256 cpu limit. Nick, growing spinlock_t to 64 bits would yield space for 64k cpus, right? I'm guessing that would be enough for a while, even for SGI.