From owner-freebsd-arm@freebsd.org Sun Feb 18 04:27:32 2018 Return-Path: Delivered-To: freebsd-arm@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 85095F0EF82 for ; Sun, 18 Feb 2018 04:27:32 +0000 (UTC) (envelope-from marklmi26-fbsd@yahoo.com) Received: from sonic304-20.consmr.mail.ne1.yahoo.com (sonic304-20.consmr.mail.ne1.yahoo.com [66.163.191.146]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 0E7A9818EC for ; Sun, 18 Feb 2018 04:27:31 +0000 (UTC) (envelope-from marklmi26-fbsd@yahoo.com) X-YMail-OSG: TcGbLLoVM1kcbNiR33P6zr.ptI9SRS0XNMiFJH1weCMzfkuEj0eoN0me58H6Svm Sc9qQKowAOgKEIW_04exUTJ5sk54uZrZfIL6ty2OTzMG99pP2mqHjem7o9zkpYXQ8r6mMN2wHJiS b5kkKLe2PvRg5MJga1H.04j45VEZJGCTOvVmf8d.70m147y7tGiHF.nC09gKpg9XhpDkWOE0cOym jQU0QbuLG0Cu7cf_A1qBN_5VI_mfqKV3bGvLS64YOWH2fnOVSSfBAB7OkixQTsXZKZ4B4ggv3ZNl L7dcGHDKLjkHh2C55CKgejnG5ppGdm34_GoRBpe3aHvWF3liYHzia6H9m9zQpuYRiZ2dkDEE6fu. 8cd1H28EIa0MbVbBvhUw9JAcCiKfUduU55L56g5daSROkkKHvZ58O_U_2kLxTFdNyqO0QgZVDJIN 2nrLEvnWMl0X.iF3nrNxVnxit3g3H8tlEzWvtzs5i6oI1UlC.ApHhjoje6qhV3H.Sl.i5 Received: from sonic.gate.mail.ne1.yahoo.com by sonic304.consmr.mail.ne1.yahoo.com with HTTP; Sun, 18 Feb 2018 04:27:25 +0000 Received: from smtp231.mail.ne1.yahoo.com (EHLO [192.168.1.25]) ([10.218.253.210]) by smtp415.mail.ne1.yahoo.com (JAMES SMTP Server ) with ESMTPA ID b1f1fa82586032edbbb7c20ac36cb2cd; Sun, 18 Feb 2018 04:27:20 +0000 (UTC) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 11.2 \(3445.5.20\)) Subject: Re: Pi3 out of swap at < 50% From: Mark Millard In-Reply-To: <20180218003840.GD93736@www.zefox.net> Date: Sat, 17 Feb 2018 20:27:19 -0800 Cc: Freebsd-arm Content-Transfer-Encoding: quoted-printable Message-Id: <926334BC-5FEE-4628-B958-9670351DA3D5@yahoo.com> References: <20180217162732.GA93736@www.zefox.net> <1518885801.91697.2.camel@freebsd.org> <9bf0ca6e-1916-3f4d-71fe-0515fe6a717f@zyxst.net> <20180218003840.GD93736@www.zefox.net> To: bob prohaska X-Mailer: Apple Mail (2.3445.5.20) X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 18 Feb 2018 04:27:32 -0000 On 2018-Feb-17, at 4:38 PM, bob prohaska wrote: > . . . > On my RPI2 running armv7 it looks like the out of swap error is real: > 2 GB are configured, around 1.5 GB are usable (limited by internal = table > sizes) and I see "out of swap" with about 1.5GB usage showing in top. >=20 > . . . If you are getting notices such as: warning: total configured swap (524288 pages) exceeds maximum = recommended amount (405460 pages). then, quoting "man 8 loader" and its kern.maxswzone material, Note that swap metadata can be fragmented, which means = that the system can run out of space before it reaches the theoretical limit. Therefore, care should be taken to = not configure more swap than approximately half of the theoretical maximum. is what that warning is about: Looking at the swapon_check_swzone code = the warning is reporting the "half" figure as "recommended", not reporting = the theoretical maximum. So, translating: "care should be taken to not configure more swap than" the reported maximum recommended amount. (If I understand correctly.) You might well be better off with around 1.5 GiBytes of swap than with 2 GiBytes of swap for an RPI2. (405460 pages is about 1.54 GiBytes.) > The best part is that a Pi2 running 11.0 managed to build world and = kernel > using 256 MB of md99 swap. It was using j2, but that's the only = difference. > IIRC it took about three days. The larger the -jN figure, the more swap is actually used at times. A = good test might be to try the old -j2 figure (or even -j1) and having about = 1.5 GiBytes of swap: find a combination that works and then explore = variations from that base-case. =3D=3D=3D Mark Millard marklmi at yahoo.com ( markmi at dsl-only.net is going away in 2018-Feb, late)