Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262732AbVAFFY5 (ORCPT ); Thu, 6 Jan 2005 00:24:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262733AbVAFFY5 (ORCPT ); Thu, 6 Jan 2005 00:24:57 -0500 Received: from ppp-217-133-42-200.cust-adsl.tiscali.it ([217.133.42.200]:19781 "EHLO dualathlon.random") by vger.kernel.org with ESMTP id S262732AbVAFFY4 (ORCPT ); Thu, 6 Jan 2005 00:24:56 -0500 Date: Thu, 6 Jan 2005 06:25:07 +0100 From: Andrea Arcangeli To: Nick Piggin Cc: Andrew Morton , riel@redhat.com, marcelo.tosatti@cyclades.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH][5/?] count writeback pages in nr_scanned Message-ID: <20050106052507.GR4597@dualathlon.random> References: <20050105173624.5c3189b9.akpm@osdl.org> <41DCB577.9000205@yahoo.com.au> <20050105202611.65eb82cf.akpm@osdl.org> <41DCC014.80007@yahoo.com.au> <20050105204706.0781d672.akpm@osdl.org> <20050106045932.GN4597@dualathlon.random> <20050105210539.19807337.akpm@osdl.org> <20050106051707.GP4597@dualathlon.random> <41DCCA68.3020100@yahoo.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <41DCCA68.3020100@yahoo.com.au> X-GPG-Key: 1024D/68B9CB43 13D9 8355 295F 4823 7C49 C012 DFA1 686E 68B9 CB43 X-PGP-Key: 1024R/CB4660B9 CC A0 71 81 F4 A0 63 AC C0 4B 81 1D 8C 15 C8 E5 User-Agent: Mutt/1.5.6i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 819 Lines: 17 On Thu, Jan 06, 2005 at 04:19:36PM +1100, Nick Piggin wrote: > This is practically what blk_congestion_wait does when the queue > isn't congested though, isn't it? The fundamental difference that makes it reliable is that: 1) only the I/O we're throttling against will be considered for the wakeup event, which means only clearing PG_writeback will be considered eligible for wakeup Currently _all_ unrelated write I/O was considered eligible for wakeup events and that could cause spurious oom kills. 2) we won't need unreliable anti-deadlock timeouts anymore - 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/