From owner-freebsd-stable@FreeBSD.ORG Thu Jul 22 03:39:27 2010 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 AFFAA1065678 for ; Thu, 22 Jul 2010 03:39:27 +0000 (UTC) (envelope-from amvandemore@gmail.com) Received: from mail-yx0-f182.google.com (mail-yx0-f182.google.com [209.85.213.182]) by mx1.freebsd.org (Postfix) with ESMTP id 685188FC1E for ; Thu, 22 Jul 2010 03:39:27 +0000 (UTC) Received: by yxe42 with SMTP id 42so2776207yxe.13 for ; Wed, 21 Jul 2010 20:39:26 -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:cc:content-type; bh=M+tZK6u5Bmjls1a8/9r6EX/SUqX6vuvlkVjSEsVVwK8=; b=pWO3WFiM1MTDKkV6tPK6mM/sQV+BgPBm4+Ds+ke0khuASj59pF0ufteR+kq6Pv/A94 Z3YSuU6G/H4Lw8oTaeF0aY38OBa9YscYYO1LBsAacOOY1eCL5NPp3E/jAUpKKI6K+CDD pOzo413rQhjC5nzYToZ43qJ+Zj5ADdwBo78t0= 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 :cc:content-type; b=avca+EF6UD1x/BhPM4nKUv0pY9wnJ/mFuS38/q81ayImbfN7aYPIvCR2Z1v/1Ah+6m 9EIu7bIthjltepD18e38tPiuzJJfMRzjXgNxC9dRtvFhVMdya+bTy4UJINQt/1bSONv6 xJYx0dCk3I15ELtWLnQz3CZZZM5q/DtMqvYIw= MIME-Version: 1.0 Received: by 10.224.66.165 with SMTP id n37mr880467qai.10.1279769966536; Wed, 21 Jul 2010 20:39:26 -0700 (PDT) Received: by 10.229.29.71 with HTTP; Wed, 21 Jul 2010 20:39:26 -0700 (PDT) In-Reply-To: References: <4C47B57F.5020309@langille.org> Date: Wed, 21 Jul 2010 22:39:26 -0500 Message-ID: From: Adam Vande More To: Dan Langille Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-stable Subject: Re: Using GTP and glabel for ZFS arrays 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: Thu, 22 Jul 2010 03:39:27 -0000 On Wed, Jul 21, 2010 at 10:34 PM, Adam Vande More wrote: > > > On Wed, Jul 21, 2010 at 10:05 PM, Dan Langille wrote: > >> Why '-b 34'? Randi pointed me to >> http://en.wikipedia.org/wiki/GUID_Partition_Table where it explains what >> the first 33 LBA are used for. It's not for us to use here. >> >> Where SOMEVALUE is the number of blocks to use. I plan not to use all the >> available blocks but leave a few hundred MB free at the end. That'll allow >> for the variance in HDD size. >> >> Any suggestions/comments? Is there any advantage to using the -l option >> on 'gpart add' instead of the glabel above? >> > > You'll want to make sure your partitions are aligned, discussion here(says > 4k drives, but info pertinent to all): > > http://lists.freebsd.org/pipermail/freebsd-hackers/2010-March/031154.html > > My understanding is that you weren't booting from zfs, just using it as an > data file system. In that case, you'd want to use "gpart add -b 512 ..." > or some other multiple of 16. Even 1024 would be a good safe number. Also > GPT creates partitions not slices. Your resulting partitions with be > labeled something like ad0p1, ad0p2, etc. > > Also if you have an applicable SATA controller, running the ahci module with give you more speed. Only change one thing a time though. Virtualbox makes a great testbed for this, you don't need to allocate the VM a lot of RAM just make sure it boots and such. -- Adam Vande More