Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763403AbZAUEib (ORCPT ); Tue, 20 Jan 2009 23:38:31 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757391AbZAUEiW (ORCPT ); Tue, 20 Jan 2009 23:38:22 -0500 Received: from qw-out-2122.google.com ([74.125.92.25]:58053 "EHLO qw-out-2122.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756962AbZAUEiV (ORCPT ); Tue, 20 Jan 2009 23:38:21 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=PlSeOKeZSd/Qb1CGfRXq96aKLhLBQztAQxoMfRqd93I+P2zrNtALwCSaPVWy4n2/N3 ENGayyZ5Vwu0yOUFxUj+Cuu3x+j6UqAksX4QZ8JlPnJb1W6oi1Cn5j8dLLmjaRu2ZXTm DEOUGAlfS1Ajecn3cpD4tA15NQqZ+d2hgJjSg= MIME-Version: 1.0 In-Reply-To: <20090121002507.GA12616@Krystal> References: <20090117004439.GA11492@Krystal> <20090117162657.GA31965@Krystal> <20090117190437.GZ30821@kernel.dk> <20090118211234.GA4913@Krystal> <20090119182654.GT30821@kernel.dk> <20090120021055.GA6990@Krystal> <20090120073709.GC30821@kernel.dk> <20090120122855.GF30821@kernel.dk> <20090120232748.GA10605@Krystal> <20090121002507.GA12616@Krystal> Date: Tue, 20 Jan 2009 23:38:19 -0500 Message-ID: <720e76b80901202038p1e1f929ci56e9f35c5a629c88@mail.gmail.com> Subject: Re: [RFC PATCH] block: Fix bio merge induced high I/O latency From: Ben Gamari To: Mathieu Desnoyers , Jens Axboe Cc: akpm@linux-foundation.org, Ingo Molnar , Linus Torvalds , linux-kernel@vger.kernel.org, ltt-dev@lists.casi.polymtl.ca Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1108 Lines: 26 On Tue, Jan 20, 2009 at 7:25 PM, Mathieu Desnoyers wrote: > * Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca) wrote: > > As a side-note : I'd like to have my results confirmed by others. Well, I think the (fixed) patch did help to some degree (I haven't done fio benchmarks to compare against yet). Unfortunately, the I/O wait time problem still remains. I have been waiting 3 minutes now for evolution to start with 88% I/O wait time yet no visible signs of progress. I've confirmed I'm using the CFQ scheduler, so that's not the problem. Also, Jens, I'd just like to point out that the problem is reproducible across all schedulers. Does your patch seek to tackle a problem specific to the CFQ scheduler, leaving the I/O wait issue for later? Just wondering. I'll post some benchmarks numbers once I have them. Thanks, - Ben -- 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/