From owner-freebsd-questions@FreeBSD.ORG Wed Jun 17 14:21:36 2015 Return-Path: Delivered-To: freebsd-questions@hub.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 54180765 for ; Wed, 17 Jun 2015 14:21:36 +0000 (UTC) (envelope-from paul@kraus-haus.org) Received: from mail-qg0-f53.google.com (mail-qg0-f53.google.com [209.85.192.53]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 1301F2E4 for ; Wed, 17 Jun 2015 14:21:35 +0000 (UTC) (envelope-from paul@kraus-haus.org) Received: by qgeu36 with SMTP id u36so15639814qge.2 for ; Wed, 17 Jun 2015 07:21:33 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:content-type:mime-version:subject:from :in-reply-to:date:content-transfer-encoding:message-id:references:to; bh=WHE4LxTw9oHupNSKWfCWuoOUToPpCmnGZpSXblS9hKc=; b=iW4qBvSzku7zRMzByN31qkhTY9uLeWzqUlJ8Iy1MLexoezM221O52/9AxMoCV0+BTq T0gLk6qBg73yIS9dTKmV3EZn1R8se05VVPQ1fqjnqLlpiqeBhKLc1zivR9xkhCmF/BHO 8pMX5Pj+hP+PVtoMfLwXAk304FRVIwhQL7LxQXf3lv0xElD+oCiArJi5LBG77pLiV30B wB1uB//KreI0sN8sHwZTryl7btpzOSwaD12KhqOndxF3pzDTsYgLQ3/p1w500q4dTCkl cs9kbKr8BWXm8RC202x5fUaQgaT+89kFsQetG0hjqqGyMH9WZTeTG+3hvOdoN1//opdN MGhw== X-Gm-Message-State: ALoCoQlfebrfhposvaEzEdsMID/5kNtlHuDUgqsOHCfWwqQU2uMuzfarX/FFvzX2blZi54/6i1VY X-Received: by 10.140.89.104 with SMTP id u95mr8109657qgd.15.1434550893712; Wed, 17 Jun 2015 07:21:33 -0700 (PDT) Received: from mbp-1.thecreativeadvantage.com (mail.thecreativeadvantage.com. [96.236.20.34]) by mx.google.com with ESMTPSA id d197sm2206980qka.21.2015.06.17.07.21.30 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 17 Jun 2015 07:21:31 -0700 (PDT) Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) Subject: Re: ZFS in a VM? From: Paul Kraus In-Reply-To: Date: Wed, 17 Jun 2015 10:21:28 -0400 Content-Transfer-Encoding: quoted-printable Message-Id: References: <9C96EB4B-A230-4A26-BDC3-067367A61E34@shire.net> <378461483.10441535.1434361136704.JavaMail.zimbra@logitravel.com> <485432824.11228956.1434438820497.JavaMail.zimbra@logitravel.com> To: FreeBSD Questions X-Mailer: Apple Mail (2.1878.6) X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 17 Jun 2015 14:21:36 -0000 On Jun 16, 2015, at 4:14, krad wrote: > Unless you are really squeezing the ram it shouldnt be a problem and = by > that i mean going below 1 GB. Its also best to stay away from 32 bit = if you > want to run zfs. I have been running ZFS on a VM for years with only 1 GB memory, but =85 0) The Host OS is FreeBSD 9.1 with VBox 1) The Guest OS is FreeBSD 9.1 2) The Guest boots from UFS, only data is on ZFS 3) The ZFS zpool is in a dedicated .vmdk file 4) The Guest has 1024 MB of memory allocated 5) I did NO tuning for ZFS 6) The Guest is running one, and only one service, SubVersion I did this so that I would have all the data integrity features of ZFS = for the data, it also make sis trivial to move the data to a different = VM (as was once needed when the original VM was compromised). I have not had any reliability issues, but the performance could = (always) be better. The ZFS ARC will grow to use any unallocated RAM and = it will scale back when necessary, but =85 if you do not have any SWAP = space configured it may not scale back fast enough and you may run out = of memory. So you _can_, whether it is a good idea in _your_ case is up to you. In = mine it is well worth it. [pkraus@svn-01 ~]$ zfs list=20 NAME USED AVAIL REFER MOUNTPOINT svn-01 34.5G 982K 42K /svn-01 svn-01/xxx 28.6G 218G 28.6G /svn-01/xxx svn-01/yyy 28.3M 218G 28.3M /svn-01/yyy svn-01/zzz 5.81G 218G 5.81G /svn-01/zzz svn-01/abc 28.7M 218G 28.7M /svn-01/abc svn-01/def 40.5K 218G 40.5K /svn-01/def [pkraus@svn-01 ~]$ zpool status pool: svn-01 state: ONLINE scan: none requested config: NAME STATE READ WRITE CKSUM svn-01 ONLINE 0 0 0 ada1p1 ONLINE 0 0 0 errors: No known data errors [pkraus@svn-01 ~]$ gpart show ada1 =3D> 34 537290173 ada1 GPT (256G) 34 537290173 1 freebsd-zfs (256G) [pkraus@svn-01 ~]$=20 -- Paul Kraus paul@kraus-haus.org