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 47DAFC433EF for ; Mon, 9 May 2022 14:29:40 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 63B536B0072; Mon, 9 May 2022 10:29:39 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 5EB3E6B0073; Mon, 9 May 2022 10:29:39 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 465856B0074; Mon, 9 May 2022 10:29:39 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 382A86B0072 for ; Mon, 9 May 2022 10:29:39 -0400 (EDT) Received: from smtpin19.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id B67EF2E947 for ; Mon, 9 May 2022 14:29:30 +0000 (UTC) X-FDA: 79446437700.19.E19A407 Received: from mail-vs1-f53.google.com (mail-vs1-f53.google.com [209.85.217.53]) by imf30.hostedemail.com (Postfix) with ESMTP id 62D67800A0 for ; Mon, 9 May 2022 14:29:13 +0000 (UTC) Received: by mail-vs1-f53.google.com with SMTP id e19so14033575vsu.12 for ; Mon, 09 May 2022 07:29:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=0ubZ2earysQ4m4NtWUTfEZKppknLOTAC4k+BzJFJ8WM=; b=NQdpueVtViIeJL0D1z9swsFzcloyZuHOtnF7FG6mux526DHz9WXMSx853jn2nEUEtl Ge+E8e9KQX92pPE4torle7+rDsLkZxnlRTsrOEHP95U097nzmNByDPXr4GVvUw++e8yp ekElvuYrv1QCM176opoAuB3gyGm6yXFUJIVxI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=0ubZ2earysQ4m4NtWUTfEZKppknLOTAC4k+BzJFJ8WM=; b=GyN3IATjikTJFxGHva3IBIw+9BlESeX7t7UQIDD+RmoU5jCFWyivRDoovI46wNYsr1 M0czSK5uj3K7tE6YaOlLBds+prfW4PQimF/zeh2ELFpS6S7nTYUi8ZSa+DvZ6Go8lGYj zNQmh1JpgWeeazWpCrsmYHdFIBVDt7dmbbr4kTVSFogM2zPWraliACrVOMC2cCOmQF3g xh8euZhfddqLSF37SSdP2A5O4uwZf+FyS9FT2kQ22Ne8mmIYacyA7Xar71OV1v/VlRxe uRoC1cMF1F7TSVNzNr3RibvQJHlZkI719LNyJkf0DrBlq1jRYS2wI3YkL+uTtfDVjdO1 4XTg== X-Gm-Message-State: AOAM530/qQjLmM9w2Xs75psLq0pNyypYL5vPCaxpcF6W58cY+0swxpub yw8TW9YQRGKIIs0F3hmCtSe0ueLmq1JcyJC+piBzNw== X-Google-Smtp-Source: ABdhPJyfzVHGS8qmhTD+a9Fv6AzA07nE/sVVpq7Wr4zE2UOc5SgzyO9l4jgcaAaAxhWTt4cA0Iajljx31sJalfmDmDk= X-Received: by 2002:a05:6102:2372:b0:32a:4ac4:5032 with SMTP id o18-20020a056102237200b0032a4ac45032mr7993808vsa.69.1652106568949; Mon, 09 May 2022 07:29:28 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Hsin-Yi Wang Date: Mon, 9 May 2022 22:29:03 +0800 Message-ID: Subject: Re: squashfs performance regression and readahea To: Matthew Wilcox Cc: Xiongwei Song , Zheng Liang , Phillip Lougher , Zhang Yi , Hou Tao , Miao Xie , Andrew Morton , Linus Torvalds , "Song, Xiongwei" , "linux-mm@kvack.org" , "squashfs-devel@lists.sourceforge.net" Content-Type: text/plain; charset="UTF-8" Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=chromium.org header.s=google header.b=NQdpueVt; spf=pass (imf30.hostedemail.com: domain of hsinyi@chromium.org designates 209.85.217.53 as permitted sender) smtp.mailfrom=hsinyi@chromium.org; dmarc=pass (policy=none) header.from=chromium.org X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 62D67800A0 X-Stat-Signature: oxxrweaurnkru9pheeskgmzyf5otfgnp X-HE-Tag: 1652106553-627511 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 Mon, May 9, 2022 at 9:21 PM 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. > > I think you shouldn't compare the performance with 4.18 directly, since there might be other factors that impact the performance. I'd suggest comparing the same kernel version with: a) with this patch b) with c1f6925e1091 ("mm: put readahead pages in cache earlier") reverted. According to https://lore.kernel.org/linux-mm/Ynfzh2ifG85MZEoN@casper.infradead.org/t/ It seems to be a 3 sec difference? 1:37.16 (1m + 37.16s) 1:04.18 1:05.28 1:06.07 1:06.31 1:06.58 1:06.80 1:06.79 1:06.95 1:06.61 > > 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.