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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F32B7C433F5 for ; Tue, 30 Nov 2021 15:40:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232761AbhK3Pn7 (ORCPT ); Tue, 30 Nov 2021 10:43:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44614 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234474AbhK3Pn5 (ORCPT ); Tue, 30 Nov 2021 10:43:57 -0500 Received: from mail-wm1-x332.google.com (mail-wm1-x332.google.com [IPv6:2a00:1450:4864:20::332]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1F8BFC06174A for ; Tue, 30 Nov 2021 07:40:38 -0800 (PST) Received: by mail-wm1-x332.google.com with SMTP id p3-20020a05600c1d8300b003334fab53afso19863216wms.3 for ; Tue, 30 Nov 2021 07:40:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:subject:from:to:cc:date:in-reply-to:references :user-agent:mime-version:content-transfer-encoding; bh=nqhuFDsnKkXRDBD2VkYSTunv9kP+Et39ou1k8Mq4Y+8=; b=NHYCWCLodTGiZBRXtkksO+9f1IGkfW+K/54xJTf4QHyMfaUQXmBq1eKy3Co9/MsCeg M8eyQmrhlIZAps3ir9vh+Cs1W0ghawJ3N2asOO25/429B8gNsKZThr/qF1XXuwju337D z4S2fkMOb5+KH1DLSy/1iXih3plROx4mFhwJfrhUffIx6QLz5Xx5jRnDx6jEnPqtrY7o mfx6uKON0aFh01e95HlDREOsHa5nCUU3s59pgZpHOH3KuHkuzoVyIaoYH1brtP7FkLJ2 6DA8nAZaYmrh7BknicjuYTUweFj4a8nDXu477XykfdakxZqqgzBhD6Lx6zS2wBx6F2Yr PaOQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:subject:from:to:cc:date:in-reply-to :references:user-agent:mime-version:content-transfer-encoding; bh=nqhuFDsnKkXRDBD2VkYSTunv9kP+Et39ou1k8Mq4Y+8=; b=kRXnv53O9i9Z6DzAESysQeDZcILyfB5YoK39hlFeNrbi2xLBxh2M8YStRQ295P/c9Z w4jrCgnZa/Ex9Xe1PA1fc06syO8rkbW+LYONcsa9M+WIxW3d3m+YyotbhFCMw75d8HO6 xVdS18n78I1qr7UMQagkEPQHABxAK0E7eqH2F78qqUAaFWv5LG0tEawpocEERYvdsCVV 5iqPkCEc+iqvpPbCY+204CbPr8F5Qmj0STm8dEF73+QCUR5t00H3bsCZrr72HEqhyb1+ oJ/IJ+U4Ygx8vHL1f3dcdorhTOsCAZD7ePf5BfazMjey/ZDwt7QXRN45PBSKKclcoxZG 6P4w== X-Gm-Message-State: AOAM531+JRDCq6dpOBpqwTXnhyyYVwJH3z8U4aaT1++AYE+DwtIezYfK eiaI+SPF78jE+pFy3M0x83I= X-Google-Smtp-Source: ABdhPJyP5t1DF+WoiL/if4a9sOp5XXpCttRBciHtZGWUzoPI3q1wdId8914BqmUlS7DtX6RP7YD1Sg== X-Received: by 2002:a1c:6a04:: with SMTP id f4mr242155wmc.56.1638286836777; Tue, 30 Nov 2021 07:40:36 -0800 (PST) Received: from p200300e94719c91f05d9351815d7236e.dip0.t-ipconnect.de (p200300e94719c91f05d9351815d7236e.dip0.t-ipconnect.de. [2003:e9:4719:c91f:5d9:3518:15d7:236e]) by smtp.googlemail.com with ESMTPSA id c4sm16775520wrr.37.2021.11.30.07.40.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 30 Nov 2021 07:40:36 -0800 (PST) Message-ID: <952443760df360b48a153c01b1dad957cd82fdea.camel@gmail.com> Subject: Re: [PATCH v2 19/20] scsi: ufs: Implement polling support From: Bean Huo To: Bart Van Assche , "Martin K . Petersen" Cc: Jaegeuk Kim , Adrian Hunter , linux-scsi@vger.kernel.org, "James E.J. Bottomley" , Bean Huo , Can Guo , Avri Altman , Stanley Chu , Asutosh Das Date: Tue, 30 Nov 2021 16:40:34 +0100 In-Reply-To: References: <20211119195743.2817-1-bvanassche@acm.org> <20211119195743.2817-20-bvanassche@acm.org> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.36.5-0ubuntu1 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org On Tue, 2021-11-30 at 06:26 -0800, Bart Van Assche wrote: > On 11/30/21 12:43 AM, Bean Huo wrote: > > On Fri, 2021-11-19 at 11:57 -0800, Bart Van Assche wrote: > > > On my test setup this patch increases IOPS from 2736 to 22000 > > > (8x) > > > for the > > > following test: > > > > > > for hipri in 0 1; do > > > fio --ioengine=io_uring --iodepth=1 --rw=randread \ > > > --runtime=60 --time_based=1 --direct=1 --name=qd1 \ > > > --filename=/dev/block/sda --ioscheduler=none --gtod_reduce=1 > > > \ > > > --norandommap --hipri=$hipri > > > done > > > > For 4KB random read, direct IO, and iodepth=1, we did not see an > > improvement in IOPS due to this patch. Maybe the test case above is > > not > > sufficient. > > Hi Bean, > > Which test has been run? Polling is only enabled if --hipri=1 is > specified > to fio and --ioengine=io_uring is the only I/O engine on Android that > supports > that flag. > > Thanks, > > Bart. Hi Bart, It is the test case in your commit message. If iodepth=1, there is no performance improvement. Increase the io-depth to multiple, for example, let iodepth= CPU core counter. I see that the interrupt overhead is significantly increased when the request is completed, so IO_polling will win compared to the interrupt mode. Kind regards, Bean