From owner-freebsd-fs@FreeBSD.ORG Wed Oct 6 07:35:31 2010 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A5EA3106566C for ; Wed, 6 Oct 2010 07:35:31 +0000 (UTC) (envelope-from torbjoern@gmail.com) Received: from mail-bw0-f54.google.com (mail-bw0-f54.google.com [209.85.214.54]) by mx1.freebsd.org (Postfix) with ESMTP id 3567B8FC14 for ; Wed, 6 Oct 2010 07:35:31 +0000 (UTC) Received: by bwz15 with SMTP id 15so6799640bwz.13 for ; Wed, 06 Oct 2010 00:35:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:content-type :content-transfer-encoding; bh=qXqmF/eDuGBrclyIH2cM3KJS42bPV0lniFDsz4WqwDc=; b=YYbgYqls75slTUfljqU02QeW7hzu1rBw1QhIkLDzUJPWPaXJlowL++MO5ZLvqNnETC Mjfp6U5a4GRE2XwrCPsFE2/835k4kiGO7CWXmnYacsA/BkR/iJDxRK4VHVpRJbH+bkR8 AEQZ49hcoFcyvpapE3SZzmaThwMIRbivRXbH4= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding; b=DS4u6Rh+59rqaRidDLKxxvfyE7zcKoEq2iAV4y7ICcmxCqA3+6iUFRXNTdgxpeLN71 FgEbpGh4ANrPKSP264tC8ICGPGFf1KrQO14zfKbmBGnVWAQLxxOz2b1gh/f4KyjUbv6c wtidueqjKWulWH2WlSBp/CUfNbgWy3TOq/Kjc= MIME-Version: 1.0 Received: by 10.204.66.79 with SMTP id m15mr9496891bki.82.1286350529450; Wed, 06 Oct 2010 00:35:29 -0700 (PDT) Received: by 10.204.71.138 with HTTP; Wed, 6 Oct 2010 00:35:29 -0700 (PDT) In-Reply-To: <4CABE9DC.7080601@DataIX.net> References: <162340.85805.qm@web113215.mail.gq1.yahoo.com> <4CABE9DC.7080601@DataIX.net> Date: Wed, 6 Oct 2010 09:35:29 +0200 Message-ID: From: Torbjorn Kristoffersen To: freebsd-fs@freebsd.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Subject: Re: Are any adjustments for ZFS necessary in 8.1 amd64? X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 06 Oct 2010 07:35:31 -0000 On Wed, Oct 6, 2010 at 5:15 AM, jhell wrote: > On 10/05/2010 20:50, Trever wrote: >> Apologies if this has been answered previously, but I can't find definit= ive info. >> >> The FBSD handbook recommends a customized loader.conf when using ZFS (fo= r all architectures): >> vm.kmem_size=3D"330M" >> vm.kmem_size_max=3D"330M" >> vfs.zfs.arc_max=3D"40M" >> vfs.zfs.vdev.cache.size=3D"5M" >> >> Is this still true for the 8.1 amd64 release? =A0I've read various place= s that it is not and that handbook is NOT up-to-date. =A0Out of the box, am= d64 8.1 ZFS so far "just works" without any customizations other than to ma= ke sure it turns on at reboot. =A0But systems are fairly quiescent, we have= not gone to production yet. >> >> In addition to the handbook recommendations, are there 8.1 amd64 tunings= that should be done for a vanilla server? =A0(Will be imap server, actuall= y.) >> >> Without tuning as per above, I see this on our systems (sysctl -a): >> vm.kmem_size: 8318648320 >> vm.kmem_size_max: 329853485875 >> vfs.zfs.arc_max: 7244906496 >> vfs.zfs.vdev.cache.size: 10485760 >> >> Our systems have 24 GB of RAM. >> > > With the amount of RAM that you have available in your system I would > not recommend using the above values that you quoted from the Wiki. > Those values from the wiki IIRC were based on a i386 system that has > less than 1G of RAM and were used as an example more than a definitive > tuning to achieve better performance. > > With all the available configurations that are possible with a ZFS based > FreeBSD system I would suggest that you try out the defaults and move > from that point onward before you try tuning for a specific scenario. It > will be best to have a definitive starting point at which you can always > refer back to in your performance testing. > I've got the same setup except 8GB of memory. I'd also like to tune as best as I can, but I'm uncertain of how far I should try to go. It's a production system so I'm playing it a bit careful. Using default settings now, but I'm also interested in better performance. TK