From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755186AbYJCClq (ORCPT ); Thu, 2 Oct 2008 22:41:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754086AbYJCClg (ORCPT ); Thu, 2 Oct 2008 22:41:36 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:49125 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754014AbYJCClf (ORCPT ); Thu, 2 Oct 2008 22:41:35 -0400 Date: Thu, 2 Oct 2008 19:40:34 -0700 From: Andrew Morton To: Nick Piggin Cc: Mikulas Patocka , linux-kernel@vger.kernel.org, linux-mm@vger.kernel.org, agk@redhat.com, mbroz@redhat.com, chris@arachsys.com Subject: Re: [PATCH] Memory management livelock Message-Id: <20081002194034.7957bccb.akpm@linux-foundation.org> In-Reply-To: <200810031232.23836.nickpiggin@yahoo.com.au> References: <20080911101616.GA24064@agk.fab.redhat.com> <20080923154905.50d4b0fa.akpm@linux-foundation.org> <200810031232.23836.nickpiggin@yahoo.com.au> X-Mailer: Sylpheed 2.4.8 (GTK+ 2.12.5; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 3 Oct 2008 12:32:23 +1000 Nick Piggin wrote: > > yup, that's pretty much unfixable, really, unless new locks are added > > which block threads which are writing to unrelated sections of the > > file, and that could hurt some workloads quite a lot, I expect. > > Why is it unfixable? Just ignore nr_to_write, and write out everything > properly, I would have thought. That can cause fsync to wait arbitrarily long if some other process is writing the file. This happens.