From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752638AbbEKHUD (ORCPT ); Mon, 11 May 2015 03:20:03 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:55986 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751378AbbEKHUA (ORCPT ); Mon, 11 May 2015 03:20:00 -0400 Date: Mon, 11 May 2015 00:20:00 -0700 From: Christoph Hellwig To: Ming Lei Cc: Christoph Hellwig , Linux Kernel Mailing List , Dave Kleikamp , Jens Axboe , Zach Brown , Maxim Patlasov , Andrew Morton , Alexander Viro , Tejun Heo Subject: Re: [PATCH v3 3/4] block: loop: use kthread_work Message-ID: <20150511072000.GB19488@infradead.org> References: <1430932106-17451-1-git-send-email-ming.lei@canonical.com> <1430932106-17451-4-git-send-email-ming.lei@canonical.com> <20150507071707.GB7595@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 07, 2015 at 06:32:03PM +0800, Ming Lei wrote: > > I can't really parse this, what's the specific advantage here? > > Patch 4's commit log provides the test data. > > >From the data, it is observed that one thread is enough to get > similar throughput with previous one which submits IO from > work concurrently. > > Single thread can decrease context switch a lots, also one thread is > often used to submit AIO in reality. But we still need to support the non-AIO case. For one due to bisectablity, and second even with AIO support we'll still have people using it.