From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.7 required=3.0 tests=FORGED_MUA_MOZILLA, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8C08CC33C9E for ; Tue, 14 Jan 2020 23:31:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6861724673 for ; Tue, 14 Jan 2020 23:31:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728774AbgANXbD (ORCPT ); Tue, 14 Jan 2020 18:31:03 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:13016 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728650AbgANXbC (ORCPT ); Tue, 14 Jan 2020 18:31:02 -0500 Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 00ENRN6m126518 for ; Tue, 14 Jan 2020 18:31:02 -0500 Received: from e06smtp05.uk.ibm.com (e06smtp05.uk.ibm.com [195.75.94.101]) by mx0a-001b2d01.pphosted.com with ESMTP id 2xhfexhqp5-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 14 Jan 2020 18:31:01 -0500 Received: from localhost by e06smtp05.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 14 Jan 2020 23:30:59 -0000 Received: from b06avi18626390.portsmouth.uk.ibm.com (9.149.26.192) by e06smtp05.uk.ibm.com (192.168.101.135) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Tue, 14 Jan 2020 23:30:56 -0000 Received: from d06av23.portsmouth.uk.ibm.com (d06av23.portsmouth.uk.ibm.com [9.149.105.59]) by b06avi18626390.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 00ENU7S026149288 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 14 Jan 2020 23:30:07 GMT Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id BB7DBA404D; Tue, 14 Jan 2020 23:30:55 +0000 (GMT) Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 890D7A4040; Tue, 14 Jan 2020 23:30:54 +0000 (GMT) Received: from localhost.localdomain (unknown [9.199.44.28]) by d06av23.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 14 Jan 2020 23:30:54 +0000 (GMT) Subject: Re: Discussion: is it time to remove dioread_nolock? To: "Theodore Y. Ts'o" , Jan Kara Cc: Xiaoguang Wang , Ext4 Developers List , joseph.qi@linux.alibaba.com, Liu Bo References: <20200109163802.GA33929@mit.edu> From: Ritesh Harjani Date: Wed, 15 Jan 2020 05:00:53 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20200109163802.GA33929@mit.edu> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 20011423-0020-0000-0000-000003A0B206 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20011423-0021-0000-0000-000021F828F8 Message-Id: <20200114233054.890D7A4040@d06av23.portsmouth.uk.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-01-14_06:2020-01-14,2020-01-14 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 impostorscore=0 lowpriorityscore=0 phishscore=0 bulkscore=0 mlxlogscore=999 clxscore=1015 suspectscore=0 malwarescore=0 mlxscore=0 priorityscore=1501 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-2001140182 Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On 1/9/20 10:08 PM, Theodore Y. Ts'o wrote: > On Thu, Jan 09, 2020 at 02:51:42PM +0530, Ritesh Harjani wrote: >>> Dbench was slightly impacted; I didn't see any real differences with >>> compilebench or postmark. dioread_nolock did improve fio with >>> sequential reads; which is interesting, since I would have expected >> >> IIUC, this Seq. read numbers are with --direct=1 & bs=2MB & ioengine=libaio, >> correct? >> So essentially it will do a DIO AIO sequential read. > > Correct. I too collected some performance numbers on my x86 box with --direct=1, bs=4K/1M & ioengine=libaio, with default opt v/s dioread_nolock opt on latest ext4 git tree. I found the delta to be within +/- 6% in all of the runs which includes, seq read, mixed rw & mixed randrw. -ritesh