From owner-freebsd-hackers@freebsd.org Wed Feb 24 18:11:14 2021 Return-Path: Delivered-To: freebsd-hackers@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 5237F564ADA for ; Wed, 24 Feb 2021 18:11:14 +0000 (UTC) (envelope-from olivier.freebsd@free.fr) Received: from smtp6-g21.free.fr (smtp6-g21.free.fr [IPv6:2a01:e0c:1:1599::15]) (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 4Dm3rZ5yvTz3v4Y; Wed, 24 Feb 2021 18:11:10 +0000 (UTC) (envelope-from olivier.freebsd@free.fr) Received: from ravel.localnet (unknown [90.118.181.206]) (Authenticated sender: olivier.freebsd@free.fr) by smtp6-g21.free.fr (Postfix) with ESMTPSA id 93DCD7802C5; Wed, 24 Feb 2021 19:11:04 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=free.fr; s=smtp-20201208; t=1614190267; bh=wOcEHQcZIFt/pP6zPFjRl6W5AE46niyVfDplHYf+mJw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Xp3Kwaj2jNmhdka8OQJ3YNbs8lfyRIarMr6PZH7yIfAbpc52GTvSFPtM/FZzk6ROU fb4LWzdLpEUyr7/ogoKj4MDFnCoGlpRn1djIRErgSt0Jsg4pzcXWQq5qKd8IooV0YA GBxBTuvWC2635FwrUfvHgkFc7uVvZe8tHTJ2K7mU+XczyG1EDdvM+wMcvahsXPwa6T ZB/5GHTB6oSpUeehfo9a7T/oLiWnjskjsi8X1+wvgtJROL2mWKqJHHjpyRDcDfXmdU rqPkKhHD7p5mxOOBE08dK7+YY2sI/9JS8DI12eZ22FSDhauFmlXYE+8LKUzSEo+xNZ kCIP991bhwPEQ== From: Olivier Certner To: Thierry Thomas Cc: freebsd-hackers@freebsd.org Subject: Re: The out-of-swap killer makes poor choices Date: Wed, 24 Feb 2021 19:11:04 +0100 Message-ID: <6928973.CEzQG83mar@ravel> In-Reply-To: References: <1984125.0OzZcVfBr4@ravel> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: 4Dm3rZ5yvTz3v4Y X-Spamd-Bar: --- Authentication-Results: mx1.freebsd.org; dkim=pass header.d=free.fr header.s=smtp-20201208 header.b=Xp3Kwaj2; dmarc=pass (policy=none) header.from=free.fr; spf=pass (mx1.freebsd.org: domain of olivier.freebsd@free.fr designates 2a01:e0c:1:1599::15 as permitted sender) smtp.mailfrom=olivier.freebsd@free.fr X-Spamd-Result: default: False [-3.00 / 15.00]; RCVD_VIA_SMTP_AUTH(0.00)[]; TO_DN_SOME(0.00)[]; R_SPF_ALLOW(-0.20)[+ip6:2a01:e0c:1:1599::15:c]; FREEMAIL_FROM(0.00)[free.fr]; DKIM_TRACE(0.00)[free.fr:+]; RCPT_COUNT_TWO(0.00)[2]; DMARC_POLICY_ALLOW(-0.50)[free.fr,none]; NEURAL_HAM_SHORT(-1.00)[-1.000]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; CTE_CASE(0.50)[]; FREEMAIL_ENVFROM(0.00)[free.fr]; ASN(0.00)[asn:12322, ipnet:2a01:e00::/26, country:FR]; RBL_DBL_DONT_QUERY_IPS(0.00)[2a01:e0c:1:1599::15:from]; DWL_DNSWL_NONE(0.00)[free.fr:dkim]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[free.fr:s=smtp-20201208]; FROM_HAS_DN(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; MIME_GOOD(-0.10)[text/plain]; SPAMHAUS_ZRD(0.00)[2a01:e0c:1:1599::15:from:127.0.2.255]; RCVD_IN_DNSWL_NONE(0.00)[2a01:e0c:1:1599::15:from]; MID_RHS_NOT_FQDN(0.50)[]; RCVD_COUNT_TWO(0.00)[2]; RCVD_TLS_ALL(0.00)[]; MAILMAN_DEST(0.00)[freebsd-hackers] X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Technical discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 24 Feb 2021 18:11:14 -0000 > For such cases, another solution exists on Linux to dynamically enlarge > the swap partition (something like dphys-swapfile or SwapSpace - see > ), but I do not know if such a > tool exists on FreeBSD? In case there is some misunderstanding: I didn't want that in my particular case. Putting the machines to a crawl for jobs that mostly were too big anyway to survive even with swap indeed proved out to be a very bad idea. Also, removing swap was for me an occasion to test whether the absence of it was causing any change in the odd OOM killer behavior I was observing (unfortunately, as said, this was not the case). That said, I wasn't aware of these tools. Interesting to know. Thanks. -- Olivier Certner