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 ACF55C25B0E for ; Tue, 16 Aug 2022 15:34:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236073AbiHPPe6 (ORCPT ); Tue, 16 Aug 2022 11:34:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50778 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236129AbiHPPef (ORCPT ); Tue, 16 Aug 2022 11:34:35 -0400 Received: from new2-smtp.messagingengine.com (new2-smtp.messagingengine.com [66.111.4.224]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6AA563AE7E; Tue, 16 Aug 2022 08:34:26 -0700 (PDT) Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailnew.nyi.internal (Postfix) with ESMTP id 280E35801C7; Tue, 16 Aug 2022 11:34:22 -0400 (EDT) Received: from imap50 ([10.202.2.100]) by compute3.internal (MEProxy); Tue, 16 Aug 2022 11:34:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= colorremedies.com; h=cc:cc:content-transfer-encoding :content-type:date:date:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:sender:subject :subject:to:to; s=fm1; t=1660664062; x=1660667662; bh=hxD2OZ44Nc hM4rhx8vDMW4CDwAVBPxREEev8zWLQ1n4=; b=Yai7Nr4mibKy1IxFv4iCgOAIFJ ggnAG+aCVwCszQEAz2H80PeQw5tL/WMZgaQ/zDiT67BC2j1usIdjn5GS80gOMcYL 0fM6a5UhhNoyBWVWBZ6oVhj6NWz/ANRYt/zEaZa2ZPA142du0lENEhUKUqtxD/1Z 8Gd+CBhlNtSpEM63xsPEnVyBumKP597rhpsuWl4oYRnBYzNuUn8BfZGlYKUxGuIQ 1cO6kRHAhGkT7yAUCx/kYBiMzumDQt6Ir18miAz/m4rJd7erUCIgTUGn+O5f88Jm /jhnjwwgpuVJ7HS3B/XNtakgLJ3P1RmKLCn9MiDfKEQ/XGAgycb4wk9kXhaA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding :content-type:date:date:feedback-id:feedback-id:from:from :in-reply-to:in-reply-to:message-id:mime-version:references :reply-to:sender:subject:subject:to:to:x-me-proxy:x-me-proxy :x-me-sender:x-me-sender:x-sasl-enc; s=fm1; t=1660664062; x= 1660667662; bh=hxD2OZ44NchM4rhx8vDMW4CDwAVBPxREEev8zWLQ1n4=; b=I sivLvqanHeFnCX2zeOZyq/BZIHzcTjc3E2japhtSG3jGy9jmJojdKEwuGpQBR+vS rUrxOwxbvfGQcOkxxWqjskDRU4jBA/QR2CtbQaPek869ztwL6hso+B5ZAM4hOmw8 iGFlmbsp/M+QscFgw3VQi/lPrQbYEvk0WnxeSlicYAYvBToUiUg1v9OCQA+x1nnB c0gbjXI00JOTpA9n04d5bJOBU6JEekjV84pIWWudn+m+Yly7xE+zkS/giquR78vJ 9s4SASepB0W0/jeI91vOoIEmQe05ykWv7ub4utq94+eAqZ5arvb0efveDnqm31Uq aNHoGtvdbfNs0Se0LVtRw== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvfedrvdehgedgleduucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne goufhushhpvggtthffohhmrghinhculdegledmnecujfgurhepofgfggfkjghffffhvfev ufgtgfesthhqredtreerjeenucfhrhhomhepfdevhhhrihhsucfouhhrphhhhidfuceolh hishhtshestgholhhorhhrvghmvgguihgvshdrtghomheqnecuggftrfgrthhtvghrnhep iefhledtudfgvdejvdfgkeelvedtfeekuefgfeehjefhgfelgfelkedvfefgffeinecuff homhgrihhnpehgohhoghhlvgdrtghomhenucevlhhushhtvghrufhiiigvpedtnecurfgr rhgrmhepmhgrihhlfhhrohhmpehlihhsthhssegtohhlohhrrhgvmhgvughivghsrdgtoh hm X-ME-Proxy: Feedback-ID: i06494636:Fastmail Received: by mailuser.nyi.internal (Postfix, from userid 501) id 6F8261700082; Tue, 16 Aug 2022 11:34:21 -0400 (EDT) X-Mailer: MessagingEngine.com Webmail Interface User-Agent: Cyrus-JMAP/3.7.0-alpha0-841-g7899e99a45-fm-20220811.002-g7899e99a Mime-Version: 1.0 Message-Id: <2b8a38fa-f15f-45e8-8caa-61c5f8cd52de@www.fastmail.com> In-Reply-To: References: <2220d403-e443-4e60-b7c3-d149e402c13e@www.fastmail.com> <61e5ccda-a527-4fea-9850-91095ffa91c4@www.fastmail.com> <4995baed-c561-421d-ba3e-3a75d6a738a3@www.fastmail.com> Date: Tue, 16 Aug 2022 11:34:00 -0400 From: "Chris Murphy" To: "Nikolay Borisov" , "Jens Axboe" , "Jan Kara" , "Paolo Valente" Cc: "Btrfs BTRFS" , Linux-RAID , linux-block , linux-kernel , "Josef Bacik" Subject: Re: stalling IO regression since linux 5.12, through 5.18 Content-Type: text/plain;charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Tue, Aug 16, 2022, at 11:25 AM, Nikolay Borisov wrote: > On 16.08.22 =D0=B3. 17:22 =D1=87., Chris Murphy wrote: >>=20 >>=20 >> On Sun, Aug 14, 2022, at 4:28 PM, Chris Murphy wrote: >>> On Fri, Aug 12, 2022, at 2:02 PM, Jens Axboe wrote: >>>> Might be worth trying to revert those from 5.12 to see if they are >>>> causing the issue? Jan, Paolo - does this ring any bells? >>> >>> git log --oneline --no-merges v5.11..c03c21ba6f4e > bisect.txt >>> >>> I tried checking out a33df75c6328, which is right before the first b= fq >>> commit, but that kernel won't boot the hardware. >>> >>> Next I checked out v5.12, then reverted these commits in order (that >>> they were found in the bisect.txt file): >>> >>> 7684fbde4516 bfq: Use only idle IO periods for think time calculatio= ns >>> 28c6def00919 bfq: Use 'ttime' local variable >>> 41e76c85660c bfq: Avoid false bfq queue merging >>>>>> a5bf0a92e1b8 bfq: bfq_check_waker() should be static >>> 71217df39dc6 block, bfq: make waker-queue detection more robust >>> 5a5436b98d5c block, bfq: save also injection state on queue merging >>> e673914d52f9 block, bfq: save also weight-raised service on queue me= rging >>> d1f600fa4732 block, bfq: fix switch back from soft-rt weitgh-raising >>> 7f1995c27b19 block, bfq: re-evaluate convenience of I/O plugging on = rq arrivals >>> eb2fd80f9d2c block, bfq: replace mechanism for evaluating I/O intens= ity >>>>>> 1a23e06cdab2 bfq: don't duplicate code for different paths >>> 2391d13ed484 block, bfq: do not expire a queue when it is the only b= usy >>> one >>> 3c337690d2eb block, bfq: avoid spurious switches to soft_rt of >>> interactive queues >>> 91b896f65d32 block, bfq: do not raise non-default weights >>> ab1fb47e33dc block, bfq: increase time window for waker detection >>> d4fc3640ff36 block, bfq: set next_rq to waker_bfqq->next_rq in waker >>> injection >>> b5f74ecacc31 block, bfq: use half slice_idle as a threshold to check >>> short ttime >>> >>> The two commits prefixed by >>> above were not previously mentioned = by >>> Jens, but I reverted them anyway because they showed up in the git l= og >>> command. >>> >>> OK so, within 10 minutes the problem does happen still. This is >>> block/bfq-iosched.c resulting from the above reverts, in case anyone >>> wants to double check what I did: >>> https://drive.google.com/file/d/1ykU7MpmylJuXVobODWiiaLJk-XOiAjSt/vi= ew?usp=3Dsharing >>=20 >> Any suggestions for further testing? I could try go down farther in t= he bisect.txt list. The problem is if the hardware falls over on an unbo= otable kernel, I have to bug someone with LOM access. That's a limited r= esource. >>=20 >>=20 > > How about changing the scheduler either mq-deadline or noop, just to s= ee=20 > if this is also reproducible with a different scheduler. I guess noop=20 > would imply the blk cgroup controller is going to be disabled I already reported on that: always happens with bfq within an hour or le= ss. Doesn't happen with mq-deadline for ~25+ hours. Does happen with bfq= with the above patches removed. Does happen with cgroup.disabled=3Dio s= et. Sounds to me like it's something bfq depends on and is somehow becoming = perturbed in a way that mq-deadline does not, and has changed between 5.= 11 and 5.12. I have no idea what's under bfq that matches this descripti= on. --=20 Chris Murphy