From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753485AbaE0U6E (ORCPT ); Tue, 27 May 2014 16:58:04 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:61329 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752215AbaE0U6B (ORCPT ); Tue, 27 May 2014 16:58:01 -0400 Message-ID: <5384FC60.1070103@fb.com> Date: Tue, 27 May 2014 14:58:08 -0600 From: Jens Axboe User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: Christoph Hellwig CC: Subject: Re: blk-mq: refactor request allocation References: <1401217190-32453-1-git-send-email-hch@lst.de> In-Reply-To: <1401217190-32453-1-git-send-email-hch@lst.de> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [192.168.57.29] X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.11.96,1.0.14,0.0.0000 definitions=2014-05-27_05:2014-05-27,2014-05-27,1970-01-01 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 spamscore=0 suspectscore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=7.0.1-1402240000 definitions=main-1405270286 X-FB-Internal: deliver Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/27/2014 12:59 PM, Christoph Hellwig wrote: > This series streamlines the request allocation path. > Series looks innocuous enough to me, but it's about a 1.5% performance drop here with an actual device. These tests are very stable, anything over ~0.1% is definitely outside of noise. I repeated and rebooted a few times and tested both, it's persistent. No smoking guns in the profile.