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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 55CB6C433EF for ; Tue, 10 May 2022 03:20:29 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 973746B0073; Mon, 9 May 2022 23:20:28 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 922476B0074; Mon, 9 May 2022 23:20:28 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7C36E6B0075; Mon, 9 May 2022 23:20:28 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 69D826B0073 for ; Mon, 9 May 2022 23:20:28 -0400 (EDT) Received: from smtpin13.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 39AA460AC2 for ; Tue, 10 May 2022 03:20:28 +0000 (UTC) X-FDA: 79448380536.13.2E58408 Received: from p3plwbeout06-03.prod.phx3.secureserver.net (p3plsmtp06-03-2.prod.phx3.secureserver.net [97.74.135.58]) by imf28.hostedemail.com (Postfix) with ESMTP id A0783C0091 for ; Tue, 10 May 2022 03:20:08 +0000 (UTC) Received: from mailex.mailcore.me ([94.136.40.141]) by :WBEOUT: with ESMTP id oGQBna3TT8LsooGQCnwJxn; Mon, 09 May 2022 20:20:24 -0700 X-CMAE-Analysis: v=2.4 cv=b653XvKx c=1 sm=1 tr=0 ts=6279d9f8 a=bheWAUFm1xGnSTQFbH9Kqg==:117 a=84ok6UeoqCVsigPHarzEiQ==:17 a=ggZhUymU-5wA:10 a=IkcTkHD0fZMA:10 a=oZkIemNP1mAA:10 a=m0AoEl9UtWfG1dJMmG4A:9 a=QEXdDO2ut3YA:10 X-SECURESERVER-ACCT: phillip@squashfs.org.uk X-SID: oGQBna3TT8Lso Received: from 82-69-79-175.dsl.in-addr.zen.co.uk ([82.69.79.175] helo=[192.168.178.33]) by smtp03.mailcore.me with esmtpa (Exim 4.94.2) (envelope-from ) id 1noGQB-0003JY-7R; Tue, 10 May 2022 04:20:23 +0100 Message-ID: <1dff431e-f51d-edb0-5abc-353ceeef50ed@squashfs.org.uk> Date: Tue, 10 May 2022 04:20:18 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.9.0 Subject: Re: squashfs performance regression and readahea To: Matthew Wilcox Cc: Xiongwei Song , Zheng Liang , Zhang Yi , Hou Tao , Miao Xie , Andrew Morton , Linus Torvalds , Hsin-Yi Wang , "Song, Xiongwei" , "linux-mm@kvack.org" , "squashfs-devel@lists.sourceforge.net" , open list References: <13af40a9-6b60-6875-8326-0827e34182d5@squashfs.org.uk> From: Phillip Lougher In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Mailcore-Auth: 439999529 X-Mailcore-Domain: 1394945 X-123-reg-Authenticated: phillip@squashfs.org.uk X-Originating-IP: 82.69.79.175 X-CMAE-Envelope: MS4xfMNMVieuczWdVBjYimVEUduAPLWl/Vg1oxlIUTN30iUUACeKH8VpzD6ksTRnFh/mh32pVyYgiuAuRtzIraY+UQ/02ovsFY4S4W0BIziBjn4ZJ6d2ldt3 1XGJv3BuJUQuhBkNIPXBtfvplAOiCs+i6MyuFpnt/En5I9045vWJPUKYOCNLwtLBrrfmBFutX2kOmfZ13IbMi1LiK6zqzvK6neU= X-Stat-Signature: bymro6phmp9ca8g88b3mi8rhrr8t59zc X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: A0783C0091 X-Rspam-User: Authentication-Results: imf28.hostedemail.com; dkim=none; spf=none (imf28.hostedemail.com: domain of phillip@squashfs.org.uk has no SPF policy when checking 97.74.135.58) smtp.mailfrom=phillip@squashfs.org.uk; dmarc=none X-HE-Tag: 1652152808-140482 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 10/05/2022 03:35, Matthew Wilcox wrote: > On Tue, May 10, 2022 at 02:11:41AM +0100, Phillip Lougher wrote: >> On 09/05/2022 14:21, Matthew Wilcox wrote: >>> On Mon, May 09, 2022 at 08:43:45PM +0800, Xiongwei Song wrote: >>>> Hi Hsin-Yi and Matthew, >>>> >>>> With the patch from the attachment on linux 5.10, ran the command as I >>>> mentioned earlier, >>>> got the results below: >>>> 1:40.65 (1m + 40.65s) >>>> 1:10.12 >>>> 1:11.10 >>>> 1:11.47 >>>> 1:11.59 >>>> 1:11.94 >>>> 1:11.86 >>>> 1:12.04 >>>> 1:12.21 >>>> 1:12.06 >>>> >>>> The performance has improved obviously, but compared to linux 4.18, the >>>> performance is not so good. >>>> >>>> Moreover, I wanted to test on linux 5.18. But I think I should revert >>>> 9eec1d897139 ("squashfs: provide backing_dev_info in order to disable >>>> read-ahead"), >>>> right? Otherwise, the patch doesn't work? >>> >>> I've never seen patch 9eec1d897139 before. If you're going to point >>> out bugs in my code, at least have the decency to cc me on it. It >>> should never have gone in, and should be reverted so the problem can >>> be fixed properly. >> >> You are not in charge of what patches goes into Squashfs, that is my >> perogative as maintainer of Squashfs. > > I think you mean 'prerogative'. And, no, your filesystem is not your > little fiefdom, it's part of a collaborative effort. > This isn't a spelling contest, and if that's the best you can do you have already failed. Be carefull here also, I have been maintainer of Squashfs for 20 years, and was kernel maintainer for both Ubuntu and Redhat for 10 years, and so I am experienced member of the community. You reply is bordering on offensive and arrogant, especially considering it is unwarranted. I did not set out to offend you, and I don't appreciate it. About 8 years ago I decided to refrain from active involvement in the kernel community, because I decided the level of discourse was disgusting, and I had enough of it. I poped up now to defend my approval of the Huawei patch. I am *quite* happy not to have any more involvement until necessary. So having said what I want to say, I will leave it at that. You have just proved why I have minimised my involvement. No doubt you'll throw your toys out the pram, but, I'm no longer listening so don't bother. >> That patch (by Huawei) fixes the performance regression in Squashfs >> by disabling readahead, and it is good workaround until something >> better. > > You *didn't even report the problem to me*. How can it be fixed if I'm > not aware of it? > There was a email discussion last year, which I responded to, and got ignored. I will find it out tomorrow, perhaps. But I will probably not bother, because life is too short. Cheers Phillip