From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kara Subject: [LSF/VM TOPIC] Writeback code cleanup & improvements Date: Wed, 24 Feb 2010 15:26:16 +0100 Message-ID: <20100224142615.GE3687@quack.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-fsdevel@vger.kernel.org To: lsf10-pc@lists.linuxfoundation.org Return-path: Received: from cantor2.suse.de ([195.135.220.15]:43076 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754566Ab0BXO0I (ORCPT ); Wed, 24 Feb 2010 09:26:08 -0500 Content-Disposition: inline Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Hi, here's one suggestion for discussion at LSF/VM summit: It seems to me that the current writeback code has outlived it's days. The code is rather complex as various tweaks accumulated over years, filesystems workaround MAX_WRITEBACK_PAGES limitation to get better performance, inode writeback is suboptimal for filesystems doing delayed allocation (we end up writing inodes twice), sync writeback is (at least in theory) livelockable. So I think it would be worthwhile to sit down and get to some agreement on how do we improve this situation. Honza -- Jan Kara SUSE Labs, CR