From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030883AbeEZApg (ORCPT ); Fri, 25 May 2018 20:45:36 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:7747 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1030802AbeEZApf (ORCPT ); Fri, 25 May 2018 20:45:35 -0400 Subject: Re: [PATCH v2] f2fs: let fstrim issue discard commands in lower priority To: Jaegeuk Kim , , References: <20180525051031.36443-1-jaegeuk@kernel.org> <20180525194916.GA52740@jaegeuk-macbookpro.roam.corp.google.com> From: Chao Yu Message-ID: <9a7e1ff0-f4b1-52b2-9849-6d2ec0a9307d@huawei.com> Date: Sat, 26 May 2018 08:45:34 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 In-Reply-To: <20180525194916.GA52740@jaegeuk-macbookpro.roam.corp.google.com> Content-Type: text/plain; charset="windows-1252" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.134.22.195] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2018/5/26 3:49, Jaegeuk Kim wrote: > The fstrim gathers huge number of large discard commands, and tries to issue > without IO awareness, which results in long user-perceive IO latencies on > READ, WRITE, and FLUSH in UFS. We've observed some of commands take several > seconds due to long discard latency. > > This patch limits the maximum size to 2MB per candidate, and check IO congestion > when issuing them to disk. > > Signed-off-by: Jaegeuk Kim It looks good to me. :) Reviewed-by: Chao Yu Thanks,