Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754002AbaGJNwy (ORCPT ); Thu, 10 Jul 2014 09:52:54 -0400 Received: from mail-wi0-f179.google.com ([209.85.212.179]:50145 "EHLO mail-wi0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753450AbaGJNww (ORCPT ); Thu, 10 Jul 2014 09:52:52 -0400 Message-ID: <53BE9AB1.6090603@kernel.dk> Date: Thu, 10 Jul 2014 15:52:49 +0200 From: Jens Axboe User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: Christoph Hellwig , Benjamin LaHaise CC: "Elliott, Robert (Server Storage)" , "dgilbert@interlog.com" , James Bottomley , Bart Van Assche , "linux-scsi@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: scsi-mq V2 References: <1403715121-1201-1-git-send-email-hch@lst.de> <20140708144829.GA5539@infradead.org> <53BD7041.5010300@interlog.com> <53BD9A24.7010203@kernel.dk> <94D0CD8314A33A4D9D801C0FE68B402958B9628B@G9W0745.americas.hpqcorp.net> <20140710062040.GB20146@infradead.org> <20140710133609.GO12478@kvack.org> <20140710135051.GA28227@infradead.org> In-Reply-To: <20140710135051.GA28227@infradead.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2014-07-10 15:50, Christoph Hellwig wrote: > On Thu, Jul 10, 2014 at 09:36:09AM -0400, Benjamin LaHaise wrote: >> There is one possible concern that could be exacerbated by other changes in >> the system: if the application is running close to the bare minimum number >> of requests allocated in io_setup(), the per cpu reference counters will >> have a hard time batching things. It might be worth testing with an >> increased number of requests being allocated if this is the case. > > Well, Robert said reverting the two aio commits didn't help. Either he > didn't manage to boot into the right kernel, or we need to look > elsewhere for the culprit. Rob, let me know what scsi_debug setup you use, and I can try and reproduce it here as well. -- Jens Axboe -- 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/