Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753576Ab3EUXuK (ORCPT ); Tue, 21 May 2013 19:50:10 -0400 Received: from mail-pd0-f178.google.com ([209.85.192.178]:46542 "EHLO mail-pd0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751139Ab3EUXuI (ORCPT ); Tue, 21 May 2013 19:50:08 -0400 Date: Wed, 22 May 2013 08:50:03 +0900 From: Tejun Heo To: Alexander Gordeev Cc: linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org, Jeff Garzik , Jens Axboe , "Nicholas A. Bellinger" Subject: Re: [PATCH RESEND 0/1] AHCI: Optimize interrupt processing Message-ID: <20130521235003.GE6985@mtj.dyndns.org> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1425 Lines: 34 Hello, Alexander. (cc'ing Jens and Nicholas, hey guys) On Tue, May 21, 2013 at 09:00:27PM +0200, Alexander Gordeev wrote: > Before this update host lock average holdtime was 3.266532061 and > average waittime was 0.009832679 [1]. After the update average > holdtime (slightly) rose up to 0.335267418 while average waittime > decreased to 0.000320469 [2]. Which means host lock with local > interrupt disabled is held roughly the same while the average > waittime dropped 30 times. > > After this update port events are handled with local interrupts > enabled and compete on individual per-port locks with average > holdtime 1.540987475 and average waittime 0.000714864 [3]. > Comparing to [1], ata_scsi_queuecmd() holds port locks 2 times > less and waits for locks 13 times less. Hmmmmmm..... I'd normally apply this patch but block layer is just growing multi-queue support and libata is likely to be converted to mq in foreseeable future, so I'm a bit hesitant to make irq handling more sophiscated right now. Would you be interested in looking into converting libata to blk mq support? I'm pretty sure it'd yield far better outcome if done properly. Thanks. -- tejun -- 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/