From owner-freebsd-hackers@freebsd.org Wed Feb 24 14:26:29 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 97D9355E958 for ; Wed, 24 Feb 2021 14:26:29 +0000 (UTC) (envelope-from rb@gid.co.uk) Received: from mx0.gid.co.uk (mx0.gid.co.uk [194.32.164.250]) by mx1.freebsd.org (Postfix) with ESMTP id 4DlysJ5XX1z3LRd; Wed, 24 Feb 2021 14:26:28 +0000 (UTC) (envelope-from rb@gid.co.uk) Received: from [194.32.164.25] ([194.32.164.25]) by mx0.gid.co.uk (8.14.2/8.14.2) with ESMTP id 11OEQLil086557; Wed, 24 Feb 2021 14:26:21 GMT (envelope-from rb@gid.co.uk) From: Bob Bishop Message-Id: <500F4BE2-87C4-45F8-85A9-326498F47CC5@gid.co.uk> Content-Type: multipart/signed; boundary="Apple-Mail=_CDE4075F-BFD0-4BB3-965F-0290FF30EDF0"; protocol="application/pgp-signature"; micalg=pgp-sha1 Mime-Version: 1.0 (Mac OS X Mail 13.4 \(3608.120.23.2.4\)) Subject: Re: The out-of-swap killer makes poor choices Date: Wed, 24 Feb 2021 14:26:20 +0000 In-Reply-To: Cc: freebsd-hackers@freebsd.org To: Thierry Thomas References: <1984125.0OzZcVfBr4@ravel> X-Mailer: Apple Mail (2.3608.120.23.2.4) X-Rspamd-Queue-Id: 4DlysJ5XX1z3LRd X-Spamd-Bar: ---- Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=pass (mx1.freebsd.org: domain of rb@gid.co.uk designates 194.32.164.250 as permitted sender) smtp.mailfrom=rb@gid.co.uk X-Spamd-Result: default: False [-4.80 / 15.00]; MID_RHS_MATCH_FROM(0.00)[]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; MV_CASE(0.50)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.20)[multipart/signed,text/plain]; HAS_ATTACHMENT(0.00)[]; RBL_DBL_DONT_QUERY_IPS(0.00)[194.32.164.250:from]; R_SPF_ALLOW(-0.20)[+mx]; SPAMHAUS_ZRD(0.00)[194.32.164.250:from:127.0.2.255]; DMARC_NA(0.00)[gid.co.uk]; NEURAL_HAM_LONG(-1.00)[-1.000]; RCPT_COUNT_TWO(0.00)[2]; NEURAL_HAM_SHORT(-1.00)[-0.999]; SIGNED_PGP(-2.00)[]; RCVD_NO_TLS_LAST(0.10)[]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+,1:+,2:~]; ASN(0.00)[asn:42831, ipnet:194.32.164.0/24, country:GB]; RCVD_COUNT_TWO(0.00)[2]; 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 14:26:29 -0000 --Apple-Mail=_CDE4075F-BFD0-4BB3-965F-0290FF30EDF0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 Hi, > On 24 Feb 2021, at 12:38, Thierry Thomas wrote: >=20 > Le mer. 24 f=C3=A9vr. 21 =C3=A0 13:02:14 +0100, Olivier Certner = > =C3=A9crivait : >=20 >> Hi, >=20 > Hello, >=20 >> 2 to 3 years ago, I stumbled against production problems on servers = doing >> heavy computations. Only a few processes (2 generally) were doing = them, and >> most of the time consumed less than 1/4 of the available RAM (2 GiB). = Apart >> from that, no other process was allocating any significant amount of = memory. >> Only some base default daemons (syslogd, cron) and sshd were running. >> Occasionally, very big jobs would come, and one or more of these = processes >> would start eating up all available memory, until FreeBSD decided = that it was >> time to take action. >=20 > 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? You can of course add swap to a running system using swapon(8), but I = have no idea whether this will improve behaviour if the system is = already low on resources. > -- > Th. Thomas. -- Bob Bishop rb@gid.co.uk --Apple-Mail=_CDE4075F-BFD0-4BB3-965F-0290FF30EDF0 Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc Content-Description: Message signed with OpenPGP -----BEGIN PGP SIGNATURE----- iF0EARECAB0WIQR+a6Wh87I/iYwcbE+8xpPppLfFvwUCYDZiDAAKCRC8xpPppLfF v6H2AKCGszzAPANOMH0st0NkTjrNc1VcZQCfcK2VMcf0P9pIsLZuR5xnHx2u6qs= =sT/v -----END PGP SIGNATURE----- --Apple-Mail=_CDE4075F-BFD0-4BB3-965F-0290FF30EDF0--