From owner-freebsd-questions@freebsd.org Sun Jul 26 20:39:26 2020 Return-Path: Delivered-To: freebsd-questions@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id D265836B1C4 for ; Sun, 26 Jul 2020 20:39:26 +0000 (UTC) (envelope-from 4250.82.1d4c20005b9b42c.b3fbdb7eb99c8e1a5fc2fb7662e6090e@email-od.com) Received: from s1-b0c6.socketlabs.email-od.com (s1-b0c6.socketlabs.email-od.com [142.0.176.198]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4BFFCw3mTjz43V7 for ; Sun, 26 Jul 2020 20:39:24 +0000 (UTC) (envelope-from 4250.82.1d4c20005b9b42c.b3fbdb7eb99c8e1a5fc2fb7662e6090e@email-od.com) DKIM-Signature: v=1; a=rsa-sha256; d=email-od.com;i=@email-od.com;s=dkim; c=relaxed/relaxed; q=dns/txt; t=1595795965; x=1598387965; h=content-transfer-encoding:content-type:mime-version:references:in-reply-to:message-id:subject:cc:to:from:date:x-thread-info; 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DKIM_TRACE(0.00)[email-od.com:+]; RCPT_COUNT_TWO(0.00)[2]; RCVD_IN_DNSWL_NONE(0.00)[142.0.176.198:from]; NEURAL_HAM_SHORT(-0.93)[-0.933]; FORGED_SENDER(0.30)[steve@sohara.org,4250.82.1d4c20005b9b42c.b3fbdb7eb99c8e1a5fc2fb7662e6090e@email-od.com]; MIME_TRACE(0.00)[0:+]; RCVD_TLS_LAST(0.00)[]; ASN(0.00)[asn:7381, ipnet:142.0.176.0/22, country:US]; FROM_NEQ_ENVFROM(0.00)[steve@sohara.org,4250.82.1d4c20005b9b42c.b3fbdb7eb99c8e1a5fc2fb7662e6090e@email-od.com]; MID_RHS_MATCH_FROM(0.00)[] X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 26 Jul 2020 20:39:26 -0000 On Sun, 26 Jul 2020 10:56:16 -0500 Valeri Galtsev wrote: > > > On 7/26/20 10:52 AM, Steve O'Hara-Smith wrote: > > On Sun, 26 Jul 2020 10:39:16 -0500 > > Valeri Galtsev wrote: > > > >> My understanding of Linux OOM killer lies along same lines though my > >> understanding is much more simplified: kill minimal number of processes > >> to recover maximum amount of resources. > > > > Not always the right thing to do though. > > > >> Another speculative way to say > >> it would be: process owning maximum amount of RAM that keeps allocating > >> more RAM is first candidate. > > > > What a pity if that is the heavy weight analytic program that > > has a run time of several hours/days and is the only thing that matters > > running on the system. > > > > And yes, I agreed with your sentiments (or judgement): killing a process > is a bad thing always. Agreed before writing any of my comments. The trouble is there really isn't anything else the OS can do because nobody ever thought to implement SIG_RELEASE_SOME_MEMORY_PLEASE which would probably be the ideal solution provided at least *some* programs responded to it. Which leaves the only variable how to choose which process to kill and there are no general rules for a good choice. -- Steve O'Hara-Smith