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=-6.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 1EFCEC47080 for ; Mon, 31 May 2021 21:33:33 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8ECA26128A for ; Mon, 31 May 2021 21:33:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8ECA26128A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D6E506B0036; Mon, 31 May 2021 17:33:31 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D1F2C6B006C; Mon, 31 May 2021 17:33:31 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C18CF8D0001; Mon, 31 May 2021 17:33:31 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0231.hostedemail.com [216.40.44.231]) by kanga.kvack.org (Postfix) with ESMTP id 8FCA36B0036 for ; Mon, 31 May 2021 17:33:31 -0400 (EDT) Received: from smtpin23.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 2FD099994 for ; Mon, 31 May 2021 21:33:31 +0000 (UTC) X-FDA: 78202827822.23.C0CC624 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf15.hostedemail.com (Postfix) with ESMTP id E5092A000252 for ; Mon, 31 May 2021 21:33:23 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 8C3316101C; Mon, 31 May 2021 21:33:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1622496809; bh=R+A87FTFXGKgzLX4fb12zuKy/NlR5s68xZJRP5jXb38=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=o8RVAYKH2fersaJpCx8kzifInSh5ue6RnlfoR9jrWezg8Y2pJAoKmn0L+5No48/nT eJkdZqjxXq888uig5QSy7uv3RN3Ddc30PivO1skzeQBNl0FB9dbbKFmJgDvOSS6vNB inhi+aXYSme/x+ozg8AF1K8Ich6s9tR318tpk/Bk= Date: Mon, 31 May 2021 14:33:29 -0700 From: Andrew Morton To: gardotd426@gmail.com Cc: bugzilla-daemon@bugzilla.kernel.org, linux-mm@kvack.org Subject: Re: [Bug 213299] New: kswapd Regression as of 5.13-rc3, eats 100% of CPU for no reason Message-Id: <20210531143329.87a1220aeb620fd253060e75@linux-foundation.org> In-Reply-To: References: X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=o8RVAYKH; spf=pass (imf15.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: E5092A000252 X-Stat-Signature: 4cu6hq9s4jeb9jzznt4b1qrnqksjws1i X-HE-Tag: 1622496803-124920 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: (switched to email. Please respond via emailed reply-to-all, not via the bugzilla web interface). On Mon, 31 May 2021 18:09:38 +0000 bugzilla-daemon@bugzilla.kernel.org wrote: > https://bugzilla.kernel.org/show_bug.cgi?id=213299 > > Bug ID: 213299 > Summary: kswapd Regression as of 5.13-rc3, eats 100% of CPU for > no reason > Product: Memory Management > Version: 2.5 > Kernel Version: 5.13-rc3, 5.13-rc4 > Hardware: All > OS: Linux > Tree: Mainline > Status: NEW > Severity: normal > Priority: P1 > Component: Slab Allocator > Assignee: akpm@linux-foundation.org > Reporter: gardotd426@gmail.com > Regression: No > > I've seen reports of kswapd0 eating up CPU, but this doesn't fit those > descriptions. > > - The bug is not present on 5.12. > > - It happens immediately on boot, CPU usage goes to 100 on all 24 threads of a > Ryzen 5900X > > - The only solution is to run `sudo pkill -9 kswapd0`. swapoff does nothing, > nor does `echo 1 > /proc/sys/vm/drop_caches`. > > - I have a swap partition and 32GB of RAM. Like I said, this happens on boot, > so nowhere *near* 32GB of RAM is being taken. And no swap is being used. This > is clearly an error in kswapd, it's like it goes completely bonkers. 5.13-rc2 > didn't have it, nor did rc1, and 5.12 doesn't have it either. > > > System Info: > > Arch Linux > Kernel: 5.13-rc3, 5.13-rc4 > Ryzen 9 5900X > 32GB DDR4-3600 > 40GB Swap partition on SSD > > sudo dmesg | grep -i swap only gives these three lines so far (after already > killing the process and about 5 min. after boot): > > [ 0.093277] Spectre V1 : Mitigation: usercopy/swapgs barriers and __user > pointer sanitization > [ 0.334800] zswap: loaded using pool lz4/z3fold > [ 2.941371] Adding 41502716k swap on /dev/sdb3. Priority:-2 extents:1 > across:41502716k SSFS > > -- > You may reply to this email to add a comment. > > You are receiving this mail because: > You are the assignee for the bug.