From owner-freebsd-stable@FreeBSD.ORG Tue Jan 3 08:05:18 2012 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 45860106566C; Tue, 3 Jan 2012 08:05:18 +0000 (UTC) (envelope-from victor@bsdes.net) Received: from equilibrium.bsdes.net (244.Red-217-126-240.staticIP.rima-tde.net [217.126.240.244]) by mx1.freebsd.org (Postfix) with ESMTP id 431AE8FC0A; Tue, 3 Jan 2012 08:05:17 +0000 (UTC) Received: by equilibrium.bsdes.net (Postfix, from userid 1001) id 074163983F; Tue, 3 Jan 2012 09:05:16 +0100 (CET) Date: Tue, 3 Jan 2012 09:05:16 +0100 From: Victor Balada Diaz To: Artem Belevich Message-ID: <20120103080515.GA36252@equilibrium.bsdes.net> References: <20120102122549.GB17398@equilibrium.bsdes.net> <20120102125929.GA89966@icarus.home.lan> <20120102134150.GC17398@equilibrium.bsdes.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Cc: freebsd-stable@freebsd.org, Jeremy Chadwick Subject: Re: Performance problems with pagedaemon X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 03 Jan 2012 08:05:18 -0000 On Mon, Jan 02, 2012 at 10:17:11AM -0800, Artem Belevich wrote: > On Mon, Jan 2, 2012 at 5:41 AM, Victor Balada Diaz wrote: > > Mysql uses more than 20G of RAM. You may want to tune it down a bit so > that there is a bit of free RAM around. > > Page daemon is trying to maintain v_free_target + v_cache_min. > > >vm.v_free_target: 161771 > >vm.v_cache_min: 161771 > > In your case that would be about 1.2GB. If 'v_free_count + > v_cache_count' are below that page daemon will periodically wake up > and will start scanning active/inactive lists trying to find the pages > it could use. In your case, when most of the memory is in active use, > page daemon's job will be almost pointless and would just waste CPU > time. > > On large memory systems default tuning for v_free/cache_min/target is > probably somewhat conservative. You may try setting them somewhat > lower via sysctl and see if you can find an equilibrium with mysql > happy, pagedaemon sleeping and the system up and running. The danger > of tuning these parameters too low is that is you don't have enough > memory available for allocation without having to sleep, things will > start falling apart and will eventually hang or crash your box. That was the problem. Thanks a lot! Is there any place or documentation about how to properly tune the VM? None of the sysctls you mentioned have description or appear to be in any man page. -- La prueba más fehaciente de que existe vida inteligente en otros planetas, es que no han intentado contactar con nosotros.