From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with ESMTP id 86CBA6B004F for ; Tue, 1 Sep 2009 16:30:25 -0400 (EDT) Date: Tue, 1 Sep 2009 16:30:22 -0400 From: Theodore Tso Subject: Re: [PATCH, RFC] vm: Add an tuning knob for vm.max_writeback_pages Message-ID: <20090901203022.GD6996@mit.edu> References: <1251600858-21294-1-git-send-email-tytso@mit.edu> <20090830165229.GA5189@infradead.org> <20090830181731.GA20822@mit.edu> <20090901180052.GA7885@think> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090901180052.GA7885@think> Sender: owner-linux-mm@kvack.org To: Chris Mason , Christoph Hellwig , linux-mm@kvack.org, Ext4 Developers List , linux-fsdevel@vger.kernel.org, jens.axboe@oracle.com List-ID: On Tue, Sep 01, 2009 at 02:00:52PM -0400, Chris Mason wrote: > > I haven't yet tried this without the max_writeback_pages patch, but the > graphs clearly show a speed improvement, and that the mainline code is > smearing writes across the drive while Jens' work is writing > sequentially. FYI, you don't need to revert the max_writebacks_pages patch; the whole point of making it a tunable was to make it easier to run benchmarks. If you want to get the effects of the original setting of MAX_WRITEBACK_PAGES before the patch, just run as root: sysctl vm.max_writeback_pages=1024 - Ted -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org