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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2764FCCF9E3 for ; Sun, 2 Nov 2025 20:54:40 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E15478E0005; Sun, 2 Nov 2025 15:54:39 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id DED4B8E0002; Sun, 2 Nov 2025 15:54:39 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D03148E0005; Sun, 2 Nov 2025 15:54:39 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id C173A8E0002 for ; Sun, 2 Nov 2025 15:54:39 -0500 (EST) Received: from smtpin02.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 6F384BBF00 for ; Sun, 2 Nov 2025 20:54:39 +0000 (UTC) X-FDA: 84066870678.02.E5E1D22 Received: from out-187.mta1.migadu.com (out-187.mta1.migadu.com [95.215.58.187]) by imf17.hostedemail.com (Postfix) with ESMTP id 6BC044000F for ; Sun, 2 Nov 2025 20:54:37 +0000 (UTC) Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=FAL7bBL+; spf=pass (imf17.hostedemail.com: domain of roman.gushchin@linux.dev designates 95.215.58.187 as permitted sender) smtp.mailfrom=roman.gushchin@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1762116877; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=vSoLTMn7D7wRI+KcjGWMGJNZbmIDanYc/C6CsZGY6C4=; b=reYZff+pdM/F6Zve8LSeiZozHttH7Z5sXF6CkudzXyjtQ3jDQxCRRdpE3T8C2fHhtYs1Rr i7RiAWKKEPTqMLQ6vl51SVDggKtEnQ61hJ+ss+0mNPJotPsgM1A/FqqtIH9RM6V+QnF+3j +vr0mJGjjcKLiu0rbjj3FStKhVz0a10= ARC-Authentication-Results: i=1; imf17.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=FAL7bBL+; spf=pass (imf17.hostedemail.com: domain of roman.gushchin@linux.dev designates 95.215.58.187 as permitted sender) smtp.mailfrom=roman.gushchin@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1762116877; a=rsa-sha256; cv=none; b=ozroIIyie/PZLA+Cjmsft1gdejhtKbLuTGo3T/Nr9i4HQ+8yf15Ui0/F7TcJUdnI0z0nbN NAtJbcfVxOfzwlylP8RYkkU+ULJ0HahIYDWYfFsSoUh/x+EoR5IfCSX6wcQwEVaKy8Tcf2 9fU6iJCTB9A6wE9EOFbYLO7oysGfhcE= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1762116875; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=vSoLTMn7D7wRI+KcjGWMGJNZbmIDanYc/C6CsZGY6C4=; b=FAL7bBL+C4exDYR5oCnLVtwAWj+9G1H9ZgsdMgNY1fT9EkYaCt1Oyygsfg30HqDWIOTChr Drhu3O+o/jfQzjrcQwvyWMuxQ1W4mQNaTYonOereiy54CtofgwkshbhVvMobBUBKFZ4/6d EroT4lTO5LUCSggGDgSv6KlmZ+MNLtg= From: Roman Gushchin To: Michal Hocko Cc: Andrew Morton , linux-kernel@vger.kernel.org, Alexei Starovoitov , Suren Baghdasaryan , Shakeel Butt , Johannes Weiner , Andrii Nakryiko , JP Kobryn , linux-mm@kvack.org, cgroups@vger.kernel.org, bpf@vger.kernel.org, Martin KaFai Lau , Song Liu , Kumar Kartikeya Dwivedi , Tejun Heo Subject: Re: [PATCH v2 00/23] mm: BPF OOM In-Reply-To: (Michal Hocko's message of "Fri, 31 Oct 2025 10:31:36 +0100") References: <20251027231727.472628-1-roman.gushchin@linux.dev> Date: Sun, 02 Nov 2025 12:53:53 -0800 Message-ID: <87ldkonoke.fsf@linux.dev> MIME-Version: 1.0 Content-Type: text/plain X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 6BC044000F X-Stat-Signature: bj8qn4dkn9c3jhq3ti56d5rpn6jeumaa X-Rspam-User: X-HE-Tag: 1762116877-26051 X-HE-Meta: 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 RbFYiuNZ taq7oYICO1KbOYksxPT41g1E71IvmPu3r6qIN21mK/FwAkHCMSnX+ijBVPwWTq3drJBBpdZ1AnU+a410/eqdiOmVlPj+xBMaHOsU548kOH2zI8kSNrGehMg6axFEAJIZr2j06RioC/VT5u/6l3mAzWLI96G9Jc5fVbgOX5Y8t+NZGIyOh+oGDkiBEHzHwvf3mw708b5jNgJciTylAiH/lLq5dJlpoOTDq2Xr80lbhxT3f8S6UqkaZ518hqQ== 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: Michal Hocko writes: > On Mon 27-10-25 16:17:03, Roman Gushchin wrote: >> The second part is related to the fundamental question on when to >> declare the OOM event. It's a trade-off between the risk of >> unnecessary OOM kills and associated work losses and the risk of >> infinite trashing and effective soft lockups. In the last few years >> several PSI-based userspace solutions were developed (e.g. OOMd [3] or >> systemd-OOMd [4]). The common idea was to use userspace daemons to >> implement custom OOM logic as well as rely on PSI monitoring to avoid >> stalls. In this scenario the userspace daemon was supposed to handle >> the majority of OOMs, while the in-kernel OOM killer worked as the >> last resort measure to guarantee that the system would never deadlock >> on the memory. But this approach creates additional infrastructure >> churn: userspace OOM daemon is a separate entity which needs to be >> deployed, updated, monitored. A completely different pipeline needs to >> be built to monitor both types of OOM events and collect associated >> logs. A userspace daemon is more restricted in terms on what data is >> available to it. Implementing a daemon which can work reliably under a >> heavy memory pressure in the system is also tricky. > > I do not see this part addressed in the series. Am I just missing > something or this will follow up once the initial (plugging to the > existing OOM handling) is merged? Did you receive patches 11-23? git send-email failed on patch 10, so I had to send the second part separately. It seems like the second part did at least to some recipients, as I got feedback to some patches from that part. In any case, you can find the whole series here: https://github.com/rgushchin/linux/tree/bpfoom.2 And thank you for reviewing the series!