From owner-freebsd-arm@freebsd.org Fri Aug 3 01:09:24 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 2C0221057483 for ; Fri, 3 Aug 2018 01:09:24 +0000 (UTC) (envelope-from fbsd@www.zefox.net) Received: from www.zefox.net (www.zefox.net [50.1.20.27]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "www.zefox.org", Issuer "www.zefox.org" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 7593D88B59 for ; Fri, 3 Aug 2018 01:09:23 +0000 (UTC) (envelope-from fbsd@www.zefox.net) Received: from www.zefox.net (localhost [127.0.0.1]) by www.zefox.net (8.15.2/8.15.2) with ESMTPS id w7319WDZ004421 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Thu, 2 Aug 2018 18:09:33 -0700 (PDT) (envelope-from fbsd@www.zefox.net) Received: (from fbsd@localhost) by www.zefox.net (8.15.2/8.15.2/Submit) id w7319WoH004420; Thu, 2 Aug 2018 18:09:32 -0700 (PDT) (envelope-from fbsd) Date: Thu, 2 Aug 2018 18:09:32 -0700 From: bob prohaska To: freebsd-arm@freebsd.org Subject: Re: RPI3 swap experiments (insufficient swap) Message-ID: <20180803010932.GA4321@www.zefox.net> References: <201807311602.w6VG2xcN072497@pdx.rh.CN85.dnsmgr.net> <20180731191016.GD94742@www.zefox.net> <23793AAA-A339-4DEC-981F-21C7CC4FE440@yahoo.com> <20180731231912.GF94742@www.zefox.net> <2222ABBD-E689-4C3B-A7D3-50AECCC5E7B2@yahoo.com> <20180801034511.GA96616@www.zefox.net> <201808010405.w7145RS6086730@donotpassgo.dyslexicfish.net> <6BFE7B77-A0E2-4FAF-9C68-81951D2F6627@yahoo.com> <20180802002841.GB99523@www.zefox.net> <20180802015135.GC99523@www.zefox.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180802015135.GC99523@www.zefox.net> User-Agent: Mutt/1.5.24 (2015-08-30) X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 03 Aug 2018 01:09:24 -0000 Just for fun, and to provide an alternate view of OOMA behavior on an RPI3, a j4 buildworld was again run with deliberately insufficient swap. A single 1 GB partition was used, on the microSD card. Having sufficient swap on microSD allows a successful -j4 buildworld. The debris I could collect is on display at http://www.zefox.net/~fbsd/rpi3/swaptests/r336877M/1gbsdflash/ The behavior suggests that OOMA misbehaves in both possible directions: It kills processes when it shouldn't, and does _not_ kill them when it should. The same behavior was observed some weeks ago, but this time it's possible to watch the gstat output. Please note that the messages Aug 1 18:08:13 www kernel: v_free_count: 5439, v_inactive_count: 1 Aug 1 18:08:25 www kernel: pid 93301 (c++), uid 0, was killed: out of swap space are stale, left over from an earlier run with swap on USB flash. There are a couple of core files included in the exhibit. At least the top session crashed with a signal 11, it happened when I was watching and I restarted top, which then ran normally until I left the console. That's a somewhat unusual occurrence, signal 11's haven't been seen on this box any time recently. I did not see what happened to tcsh, but it left one core file. In the end the console carried a stream of what look like hardware errors referencing da0, but all was forgiven after reboot and a couple cycles of fsck -fy. An excerpt is in the readme file. One curiosity is that the system remained responsive to ping. The console wasn't responsive, ssh sessions either disconnected or froze. Power-cycling was the only way to reboot. Thanks for reading, I hope the observations are of some use. bob prohaska