From owner-freebsd-questions@freebsd.org Sat Feb 18 13:12:48 2017 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 479D5CE3269 for ; Sat, 18 Feb 2017 13:12:48 +0000 (UTC) (envelope-from bennett@sdf.org) Received: from mx.sdf.org (mx.sdf.org [205.166.94.20]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "ol.sdf.org", Issuer "ol.sdf.org" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 2657D1692 for ; Sat, 18 Feb 2017 13:12:47 +0000 (UTC) (envelope-from bennett@sdf.org) Received: from sdf.org (IDENT:bennett@otaku.freeshell.org [205.166.94.9]) by mx.sdf.org (8.15.2/8.14.5) with ESMTPS id v1IDCM6Z011020 (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256 bits) verified NO); Sat, 18 Feb 2017 13:12:22 GMT Received: (from bennett@localhost) by sdf.org (8.15.2/8.12.8/Submit) id v1IDCLUc025629; Sat, 18 Feb 2017 07:12:21 -0600 (CST) From: Scott Bennett Message-Id: <201702181312.v1IDCLUc025629@sdf.org> Date: Sat, 18 Feb 2017 07:12:21 -0600 To: freebsd@qeng-ho.org Subject: Re: pf can't get memory for tables Cc: freebsd-questions@freebsd.org References: <201702170919.v1H9J45t015787@sdf.org> <1cd15985-dcf5-673f-9517-63575c8fbf1e@qeng-ho.org> In-Reply-To: <1cd15985-dcf5-673f-9517-63575c8fbf1e@qeng-ho.org> User-Agent: Heirloom mailx 12.5 6/20/10 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 18 Feb 2017 13:12:48 -0000 Arthur Chance wrote: > On 17/02/2017 09:19, Scott Bennett wrote: > [much snippage] > > > After > > puzzling over this turn of events on my screen for several seconds...aha! > > The machine has only 4 GB of RAM, so a long while back I added > > > > vm.kmem_size_max=805306368 > > > > to /boot/loader.conf in order to limit the tendency at the time for ZFS to > > take over everything with a growing ARC. Unfortunately, vm.kmem_size_max > > is one of those tunables that can only be set at boot time, so I can't easily > > experiment with increasing the value. > > If you want to control the ARC size, surely setting vfs.zfs.arc_max in > /boot/loader.conf is more specific than vm.kmem_size_max? Unfortunately > that's a boot time tunable as well. > The problem with vfs.zfs.arc_max is that it is one of several tunables that are not available when zfs.ko is not currently loaded (or compiled into the kernel). There are some situations from time to time where I don't want ZFS present, so I unload the module before continuing the boot sequence, and then if vfs.zfs.arc_max is specified in /boot/loader.conf, it results in an error condition and message. vm.kmem_size_max may seem a bit ham-handed, but it does do the job whether ZFS is present or not. Scott Bennett, Comm. ASMELG, CFIAG ********************************************************************** * Internet: bennett at sdf.org *xor* bennett at freeshell.org * *--------------------------------------------------------------------* * "A well regulated and disciplined militia, is at all times a good * * objection to the introduction of that bane of all free governments * * -- a standing army." * * -- Gov. John Hancock, New York Journal, 28 January 1790 * **********************************************************************