Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755873AbXJBN1S (ORCPT ); Tue, 2 Oct 2007 09:27:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753024AbXJBN1K (ORCPT ); Tue, 2 Oct 2007 09:27:10 -0400 Received: from smtp.ustc.edu.cn ([202.38.64.16]:37180 "HELO ustc.edu.cn" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with SMTP id S1752958AbXJBN1J (ORCPT ); Tue, 2 Oct 2007 09:27:09 -0400 Message-ID: <391331626.16970@ustc.edu.cn> X-EYOUMAIL-SMTPAUTH: wfg@mail.ustc.edu.cn Date: Tue, 2 Oct 2007 21:27:02 +0800 From: Fengguang Wu To: Andrew Morton Cc: Chuck Ebbert , Greg KH , Chakri n , Peter Zijlstra , Krzysztof Oledzki , linux-pm , lkml , richard kennedy , Ingo Molnar Subject: Re: [PATCH] writeback: avoid possible balance_dirty_pages() lockup on a light-load bdi Message-ID: <20071002132702.GA10967@mail.ustc.edu.cn> References: <92cbf19b0709272332s25684643odaade0e98cb3a1f4@mail.gmail.com> <391063897.19256@ustc.edu.cn> <470118EE.1020103@redhat.com> <391290444.23950@ustc.edu.cn> <20071001191457.2f7c7538.akpm@linux-foundation.org> <20071002121327.GA5718@mail.ustc.edu.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20071002121327.GA5718@mail.ustc.edu.cn> X-GPG-Fingerprint: 53D2 DDCE AB5C 8DC6 188B 1CB1 F766 DA34 8D8B 1C6D User-Agent: Mutt/1.5.16 (2007-06-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 695 Lines: 15 On Tue, Oct 02, 2007 at 08:13:27PM +0800, Fengguang Wu wrote: [...] > One more serious problem is, a busy writer could also drain all the > dirty pages and make (nr_writeback == dirty_limit+1MB). In that case, > I suspect the light-load sdb writer still have good chance to > make progress(need confirmation). Well it seems to be a really tricky issue without knowing the per-bdi numbers. Maybe we could just encourage users to upgrade to 2.6.24... - 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/