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 73836C5475B for ; Tue, 20 Feb 2024 18:51:49 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 03E716B0098; Tue, 20 Feb 2024 13:51:49 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id F304D6B0099; Tue, 20 Feb 2024 13:51:48 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DD0F46B009A; Tue, 20 Feb 2024 13:51:48 -0500 (EST) 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 CDA2B6B0098 for ; Tue, 20 Feb 2024 13:51:48 -0500 (EST) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id A4ABB40816 for ; Tue, 20 Feb 2024 18:51:48 +0000 (UTC) X-FDA: 81813076296.26.17787CE Received: from mail-ua1-f45.google.com (mail-ua1-f45.google.com [209.85.222.45]) by imf17.hostedemail.com (Postfix) with ESMTP id E254A40014 for ; Tue, 20 Feb 2024 18:51:46 +0000 (UTC) Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=ZnidwJpB; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf17.hostedemail.com: domain of elver@google.com designates 209.85.222.45 as permitted sender) smtp.mailfrom=elver@google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1708455106; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=B/Y907SBVrsllYy6qByqNQHwt7IG5OvmGpDMhx82aEA=; b=qNGAhziNX2QS3+s/7/5Ja8lyQT7CRCEETQypwBK0M7D1UAXQ0sfYi5rMjPRXIsqBz4dBs8 2S7E2+uVwNotTohnjFv6/YH010mMFnALmLa7hGXOAy+4Kz39m5pl8xVEEODSSIdMaQNwts XY04RtPW+ViozXGXVF7kKANyWO6BXPw= ARC-Authentication-Results: i=1; imf17.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=ZnidwJpB; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf17.hostedemail.com: domain of elver@google.com designates 209.85.222.45 as permitted sender) smtp.mailfrom=elver@google.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1708455106; a=rsa-sha256; cv=none; b=IG2hoIWJPH//fHUYE5w0i5y4p0T29myqatctfuoV2pRKYZXutqyFX8A6sssFoQBjwD7KSH OZJnwgMyOJbPCv7GB7v3aIkz4d2J5kTEGaUmQoS2dfSWaXE1o8/ahuXYEyiZ36PihWuMSa NmzFhLS4wX/8dRkvltSBvaVwLORAGio= Received: by mail-ua1-f45.google.com with SMTP id a1e0cc1a2514c-7d625a3ace6so3772695241.0 for ; Tue, 20 Feb 2024 10:51:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1708455106; x=1709059906; darn=kvack.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=B/Y907SBVrsllYy6qByqNQHwt7IG5OvmGpDMhx82aEA=; b=ZnidwJpBVCUuif/DbGmwX2Z6BfyINu6sRQFxOQEyitiQeGNHmmYwh+9xTV9HzZnSSU 0G5OaFxHhbav2aq1UnYeU9uTseAdKS8pY1Ve22kO+Qdt7m0osgBRMUSu58f1Rg+8HgAn hPcoV5+HSDipCN6vod1a5XKbgrRYTmLG5S7JLoP8Hfuyzw7Nd00q+tMpjmQ6JIPQFyeK 3OpeLbbV0+7A7+NCUR3aZuIZL2sefrVWSs+MFk1j8HW7RHfC6XvIXS4g6qfLVnvXObcb hjsHgzB+vSpafmp0scc0SQ8zI/MzouvOILcB42BiFEiBKGfCohRwB3F4x6M+pHxJUjUF MrPw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1708455106; x=1709059906; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=B/Y907SBVrsllYy6qByqNQHwt7IG5OvmGpDMhx82aEA=; b=t2MLV6W+aGGnGjxCx+uKWr93LvpyMEFhEnXJTiZj61BnnenIc5OglUpgRhao00J50G O1+gdAWs81l63SWP2lWXGtyUYuEpmw+i4v05oSljCUe3StG3+FKviAeMi83/7mUHll0T Bk5TW/DeNpZbmMzT48yLi1i73KggheWuOJafE7mzUDAiTNBzRheT3CD9PtuaXK/0dfgD 3ZXUOjiDm9FeTaZqhli7R983Sza/Lg/U6lntYnkGpRyoEElBKw5OyGwAZlQhVeeSaMBF 2lecD7RdkMgu8LgLdV9wcHuxiQa8Py8u1dLCb6XhHilRYOWrPmg+p/RbbUw0ChosAmTv dwzg== X-Forwarded-Encrypted: i=1; AJvYcCUO9KzLHQy7+pakFyjobrp/THkiNDgPzuv7cyCGAeW5udhh0OPGI3Aq+NuLof3mmy1LsS9eEvsEzo3bmG8Hunm3HH8= X-Gm-Message-State: AOJu0Yy5SUng1TWIynuXp51RaZigJp5Knv06E6R+Dwk5JW/iclmf3wWB MflPIq0SqBLFiY5vORdFtnNjrXZJeoDmEpuOomwe7FinZVfO3dmnBrHCVv0k6xeAYaVlYB46ls3 TmjObu0nR425PxPc4+NKmPDTdTt7Vax/xoYgo X-Google-Smtp-Source: AGHT+IFHzuL7PAZHpU0n+2ypxN9ERpiX5mLfFdtADHU+PKGjyMPtDiVJEcCfRQjX0yyY7/Q65ionVkALzA1P/jMzi1Q= X-Received: by 2002:a05:6102:1608:b0:470:5718:23a7 with SMTP id cu8-20020a056102160800b00470571823a7mr5778068vsb.7.1708455105738; Tue, 20 Feb 2024 10:51:45 -0800 (PST) MIME-Version: 1.0 References: <91c50335-e7b6-4ae1-9dad-a0c990b52021@suse.cz> <20240219152836.11d36709c594e66fe3037f2d@linux-foundation.org> <7e31accb-db01-486f-afb8-18a3f5402d00@suse.cz> <20240220093011.bf84486d704c3814079c2aa0@linux-foundation.org> <96c51d35-15ce-42d0-b81b-7e76044e1f2b@suse.cz> In-Reply-To: <96c51d35-15ce-42d0-b81b-7e76044e1f2b@suse.cz> From: Marco Elver Date: Tue, 20 Feb 2024 19:51:07 +0100 Message-ID: Subject: Re: regression/bisected commit 773688a6cb24b0b3c2ba40354d883348a2befa38 make my system completely unusable under high load To: Vlastimil Babka Cc: Andrew Morton , Mikhail Gavrilov , Andrey Konovalov , glider@google.com, dvyukov@google.com, eugenis@google.com, Oscar Salvador , Linux List Kernel Mailing , Linux Memory Management List Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: E254A40014 X-Rspam-User: X-Rspamd-Server: rspam02 X-Stat-Signature: tdafq8q4kwkwdu7a59o7ur1digmhn76t X-HE-Tag: 1708455106-444661 X-HE-Meta: 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 xzo6RGMB zR2fVKMyS28OAMaKzcjXLcgUhLzGX5h7Yj/x2nNxY1oFq0j+oaeaH6BTq0urtd4wVl7ZM 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: List-Subscribe: List-Unsubscribe: On Tue, 20 Feb 2024 at 19:16, Vlastimil Babka wrote: > > On 2/20/24 18:30, Andrew Morton wrote: > > On Tue, 20 Feb 2024 10:37:03 +0500 Mikhail Gavrilov wrote: > > > >> On Tue, Feb 20, 2024 at 4:50=E2=80=AFAM Vlastimil Babka wrote: > >> > > > >> > > I'm all confused. > >> > > > >> > > 4434a56ec209 ("stackdepot: make fast paths lock-less again") was > >> > > mainlined for v6.8-rc3. > >> > > >> > Uh sorry, I just trusted the info that it's not merged and didn't ve= rify > >> > it myself. Yeah, I can see it is there. > >> > > >> > >> Wait, I am talk about these two patches which is not merged yet: > >> [PATCH v2 1/2] stackdepot: use variable size records for non-evictable= entries > >> [PATCH v2 2/2] kasan: revert eviction of stack traces in generic mode > >> https://lore.kernel.org/linux-mm/20240129100708.39460-1-elver@google.c= om/ > > > > A can move those into the 6.8-rc hotfixes queue, and it appears a > > cc:stable will not be required. > > > > However I'm not seeing anything in the changelogs to indicate that > > we're fixing a dramatic performance regression, nor why that > > regressions is occurring. It's primarily fixing a regression of memory usage overhead for stackdepot users in general. Performance is mostly fixed, but patch 2/2 ("kasan: revert eviction of stack traces in generic mode") also helps with KASAN performance because entries that were being repeatedly evicted-then-reallocated are just allocated once and with increasing system uptime the slow path will be taken much less. > We also seem have an unhappy bot with the 2/2 patch :/ although it's not = yet > clear if it's a genuine issue. > > https://lore.kernel.org/all/202402201506.b7e4b9b6-oliver.sang@intel.com/ While it would be nice if 6.8 would not regress over 6.7 (performance is mostly fixed, memory usage is not), waiting for confirmation what the rcutorture issue from the bot is about might be good. Mikhail: since you are testing mainline, in about 4 weeks the fixes should then reach 6.9-rc in the next merge window. Until then, if it's not too difficult for you, you can apply those 2 patches in your own tree. Thanks, -- Marco