From owner-freebsd-stable@FreeBSD.ORG Wed Dec 26 20:29:55 2007 Return-Path: Delivered-To: stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 5452816A419 for ; Wed, 26 Dec 2007 20:29:55 +0000 (UTC) (envelope-from gemini@geminix.org) Received: from geminix.org (geminix.org [213.73.82.81]) by mx1.freebsd.org (Postfix) with ESMTP id 1AFFD13C4E1 for ; Wed, 26 Dec 2007 20:29:50 +0000 (UTC) (envelope-from gemini@geminix.org) Message-ID: <4772B5EC.30807@geminix.org> Date: Wed, 26 Dec 2007 21:13:32 +0100 From: Uwe Doering Organization: Private UNIX Site User-Agent: Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.8.1.11) Gecko/20071201 SeaMonkey/1.1.7 MIME-Version: 1.0 To: Mike Tancsa References: <200712220531.WAA09277@lariat.net> <476FBED0.2080400@samsco.org> <200712241549.IAA19650@lariat.net> <476FDA10.4060107@samsco.org> <200712241653.JAA20845@lariat.net> <476FE868.8080704@samsco.org> <200712241723.lBOHNLtt049769@lava.sentex.ca> <477252E4.4070707@samsco.org> <200712261740.lBQHetRB061995@lava.sentex.ca> In-Reply-To: <200712261740.lBQHetRB061995@lava.sentex.ca> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Received: from gemini by geminix.org with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.68 (FreeBSD)) (envelope-from ) id 1J7cdA-000PEi-NI; Wed, 26 Dec 2007 21:29:49 +0100 Cc: stable@freebsd.org Subject: Re: SMP on FreeBSD 6.x and 7.0: Worth doing? 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: Wed, 26 Dec 2007 20:29:55 -0000 Mike Tancsa wrote: > At 08:11 AM 12/26/2007, Scott Long wrote: >>> How does one know if the vfs.ufs.dirhash_maxmem is set too >>> high and are exhausting KVA ? >> >> Panics, freezes, failure to exec new programs, failure to create >> pipes, etc. > > Is there anyway to know ahead of time one is getting close to the stage > where all those "bad things" start to happen ? At least on FreeBSD 4.11 you can do sysctl -a|grep kvm and get something like this: vm.kvm_size: 1065353216 vm.kvm_free: 348127232 Perhaps this works on later versions of FreeBSD, too. Now, if vm.kvm_free drops to 10% or so of vm.kvm_size and continues to fall, and vfs.ufs.dirhash_mem still hasn't hit the vfs.ufs.dirhash_maxmem limit, it's time to get concerned. Of course, you can also use the vm.kvm_* values to dimension vfs.ufs.dirhash_maxmem properly in the first place. Regards, Uwe -- Uwe Doering | EscapeBox - Managed On-Demand UNIX Servers gemini@geminix.org | http://www.escapebox.net