From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267663AbUBTBnW (ORCPT ); Thu, 19 Feb 2004 20:43:22 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267686AbUBTBnV (ORCPT ); Thu, 19 Feb 2004 20:43:21 -0500 Received: from mail-07.iinet.net.au ([203.59.3.39]:14810 "HELO mail.iinet.net.au") by vger.kernel.org with SMTP id S267663AbUBTBkq (ORCPT ); Thu, 19 Feb 2004 20:40:46 -0500 Message-ID: <40356599.3080001@cyberone.com.au> Date: Fri, 20 Feb 2004 12:40:41 +1100 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040122 Debian/1.6-1 X-Accept-Language: en MIME-Version: 1.0 To: Andrew Morton CC: miquels@cistron.nl, axboe@suse.de, linux-lvm@sistina.com, linux-kernel@vger.kernel.org, thornber@redhat.com Subject: Re: [PATCH] per process request limits (was Re: IO scheduler, queue depth, nr_requests) References: <20040216133047.GA9330@suse.de> <20040217145716.GE30438@traveler.cistron.net> <20040218235243.GA30621@drinkel.cistron.nl> <20040218172622.52914567.akpm@osdl.org> <20040219021159.GE30621@drinkel.cistron.nl> <20040218182628.7eb63d57.akpm@osdl.org> <20040219101519.GG30621@drinkel.cistron.nl> <20040219101915.GJ27190@suse.de> <20040219205907.GE32263@drinkel.cistron.nl> <40353E30.6000105@cyberone.com.au> <20040219235303.GI32263@drinkel.cistron.nl> <40355F03.9030207@cyberone.com.au> <20040219172656.77c887cf.akpm@osdl.org> In-Reply-To: <20040219172656.77c887cf.akpm@osdl.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andrew Morton wrote: >Nick Piggin wrote: > >>Even with this patch, it might still be a good idea to allow >>pdflush to disregard the limits... >> > >Has it been confirmed that pdflush is blocking in get_request_wait()? I >guess that can happen very occasionally because we don't bother with any >locking around there but if it's happening a lot then something is bust. > > Miquel's analysis is pretty plausible, but I'm not sure if he's confirmed it or not, Miquel? Even if it isn't happening a lot, and something isn't bust it might be a good idea to do this.