From owner-freebsd-hackers@FreeBSD.ORG Sat Jan 23 16:19:48 2010 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 4E9A01065670 for ; Sat, 23 Jan 2010 16:19:48 +0000 (UTC) (envelope-from jhellenthal@gmail.com) Received: from mail-qy0-f174.google.com (mail-qy0-f174.google.com [209.85.221.174]) by mx1.freebsd.org (Postfix) with ESMTP id EB8BC8FC12 for ; Sat, 23 Jan 2010 16:19:47 +0000 (UTC) Received: by qyk4 with SMTP id 4so1198155qyk.7 for ; Sat, 23 Jan 2010 08:19:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:sender:date:from:to:cc :subject:in-reply-to:message-id:references:user-agent :x-openpgp-key-id:x-openpgp-key-fingerprint:mime-version :content-type:content-transfer-encoding; bh=wxuEPhxRsiFSQgUycmLs6sgRxd3VgwAFSD/yNdusxmo=; b=A52tJp/g2KVxnlSel6tNUbDxulBi6F83oiAbwHAsXPRseakl6a2Ji//gNSYvBWogeQ +b6NF/ukq5LF+4yxGaUleRlgGxSVGIcRISJIdouMcXMk/GC4p3tO8SiIS3OGzKzPW7Uy umq3fTH3i+BBTYfaUhKONdjkkAjXIGBWjF8l4= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:date:from:to:cc:subject:in-reply-to:message-id:references :user-agent:x-openpgp-key-id:x-openpgp-key-fingerprint:mime-version :content-type:content-transfer-encoding; b=xkh8yGvb4nlS4E6C/ql+nnbjDetZyCAulMY6X5Wpi2JPI7GrdtJ89ciHKgyMKvtD3I v3QweXJ6hfsn+5mfiZHknO3zmct7Iab9nzJ7BPv6F3INwx/cNlPT1NenKXpZQ60XWtKM EeONa/RiCuDAUUG6Tn3U1Fkse2YEYNzarN+2k= Received: by 10.224.85.5 with SMTP id m5mr1329924qal.97.1264263587032; Sat, 23 Jan 2010 08:19:47 -0800 (PST) Received: from centel.dataix.local (ppp-21.34.dialinfree.com [209.172.21.34]) by mx.google.com with ESMTPS id 6sm7617637qwk.21.2010.01.23.08.19.42 (version=TLSv1/SSLv3 cipher=RC4-MD5); Sat, 23 Jan 2010 08:19:45 -0800 (PST) Sender: "J. Hellenthal" Date: Sat, 23 Jan 2010 11:19:33 -0500 From: jhell To: Artem Belevich In-Reply-To: Message-ID: References: <7f14551c1001190119x46c6b04dx2362cd1252f0d81@mail.gmail.com> <7f14551c1001190216w49814186n1ada2b721380502b@mail.gmail.com> <4B55C5A6.2020109@DataIX.net> <20100120111433.25801pnmhrxnirok@webmail.leidinger.net> User-Agent: Alpine 2.00 (BSF 1167 2008-08-23) X-OpenPGP-Key-Id: 0x89D8547E X-OpenPGP-Key-Fingerprint: 85EF E26B 07BB 3777 76BE B12A 9057 8789 89D8 547E MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8BIT Cc: Alexander Leidinger , FreeBSD Hackers Subject: Re: Setting "zfs_arc_max" value in FreeBSD 8. X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 23 Jan 2010 16:19:48 -0000 On Sat, 23 Jan 2010 00:19, fbsdlist@ wrote: > Good to hear that it's usable for you even on a relatively low-memory > system. Now, throw in an SSD for L2ARC, more RAM for ARC (and L2ARC > housekeeping) and then it starts to really shine. > Can not wait until I can get something like this spinning!. I'm looking at around 6 months before this type of configuration will come into effect and be viable. I'm excited!. > As for better than expected performance, in my not-so scientific > benchmarks (copying 10G-large files on 8-disk RAIDZ2 pool until > filesystem is full) ZFS on FreeBSD did beat the hell out of > OpenSolaris on the same hardware. I was really surprised. I'm sure > something needed to be tuned on OpenSolaris, but it was nice to see > FreeBSD performing so well. > > --Artem > These guys really are doing one hell (maybe 2 or 3 ;]) of a job. Couldn't ask for better people to work on this. > > > On Fri, Jan 22, 2010 at 6:39 PM, jhell wrote: >> >> On Fri, 22 Jan 2010 11:47, fbsdlist@ wrote: >>>>> >>>>> Anyone know if it is adjustable on a system with 1024MB of ram ? Is this >>>>> just being auto calculated by some other value ? >>> >>> You may want to make sure that vm.kmem_size is set to a value much >>> larger than vfs.zfs.arc_max. Default value may be too small to allow >>> such a large ARC. >>> >>> On a side note, I'm not sure that ZFS is a good match for system with >>> only 1G of RAM. By trial and error on my box with 8G or memory I've >>> figured out that I need to set arc_max ~1G below physical memory size >>> to avoid lockups under load. YMMV. >>> >> >> ZFS on this box with 1G has been quite enjoyable actually. With the settings >> I have posted I have not had any lockup on stable/7 and no sudden freezes or >> waits for transfers. So this entirely thus far has been a godsend. I had >> even put this thing through some of the tortures that others have posted to >> the list and not come up with the same results but better. There is >> obviously a lot of variables in this between hardware and configurations >> used so the results are minimal in comparison. With ZFS in place on this >> machine it performs a little bit under specs for the hardware but I wouldn't >> expect anything less for such a file-system. >> >> -- >> >>  Thoughts & Prayers out to Haiti. >> >>  jhell >> >> > _______________________________________________ > freebsd-hackers@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-hackers > To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.org" > -- jhell