From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([208.92.234.80] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1Q8Xzn-0002rT-9V for garchives@archives.gentoo.org; Sat, 09 Apr 2011 13:14:38 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 4A4841C01F; Sat, 9 Apr 2011 13:11:56 +0000 (UTC) Received: from mail-wy0-f181.google.com (mail-wy0-f181.google.com [74.125.82.181]) by pigeon.gentoo.org (Postfix) with ESMTP id ED22E1C01F for ; Sat, 9 Apr 2011 13:11:50 +0000 (UTC) Received: by wyi11 with SMTP id 11so5355737wyi.40 for ; Sat, 09 Apr 2011 06:11:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:from:to:subject:date:user-agent:cc:references :in-reply-to:mime-version:content-type:content-transfer-encoding :message-id; bh=NeeRwawnoPzEwtHl502Mb/Lbe6ZST3Ms31YEhs6D7/Q=; b=jq9kT9mEvqdMeMK/KgaWDFwChJHVykbeu/aD04ze/O9wSpAB/3WFDfVkXPHGjS42V4 EJjnV0dIgVbB4bXAyBUzmELkXjA8wkJ0LABxeHe/DBQHtPneCwd3NQ0BBN4VVZh761w5 Fczp3iyAW3iB8Dkok6gAUYBNXZ0oNROSG+3NM= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:subject:date:user-agent:cc:references:in-reply-to :mime-version:content-type:content-transfer-encoding:message-id; b=hXuw6zuc9ilb3hEizp4ofaFVuLxVBkoMpFclYEvSc+qOtNZVSw7kpXZu01r1TqC3wq FGwCUE2j6DHZrJmTguT0NrugEkAeZak2ZXfEz3bhkea8KAwMQcgItoxph5DhA1x5c/wV a4mWLbzwvY6U2XlIO2BELhlI6DJ3OBx2plkRs= Received: by 10.216.142.35 with SMTP id h35mr852444wej.31.1302354710252; Sat, 09 Apr 2011 06:11:50 -0700 (PDT) Received: from nazgul.localnet (196-215-19-231.dynamic.isadsl.co.za [196.215.19.231]) by mx.google.com with ESMTPS id bs4sm2267146wbb.18.2011.04.09.06.11.48 (version=TLSv1/SSLv3 cipher=OTHER); Sat, 09 Apr 2011 06:11:49 -0700 (PDT) From: Alan McKinnon To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] LVM for data drives but not the OS Date: Sat, 9 Apr 2011 15:11:30 +0200 User-Agent: KMail/1.13.6 (Linux/2.6.38-ck; KDE/4.6.2; x86_64; ; ) Cc: Dale References: <4D9D9071.2050504@gmail.com> <201104091319.10422.alan.mckinnon@gmail.com> <4DA0465D.2000409@gmail.com> In-Reply-To: <4DA0465D.2000409@gmail.com> Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201104091511.30765.alan.mckinnon@gmail.com> X-Archives-Salt: X-Archives-Hash: 5a420a0088719ab5d35b4afb2968419d Apparently, though unproven, at 13:43 on Saturday 09 April 2011, Dale did opine thusly: > So, when I get me a new drive, I use pvcreate to get it ready for LVM, > then use vgextend to add it to the VG, then it is available for whatever > LV I want to extend or to make a new LV? Yup, that's really what it's all about. LVM will decide for itself what bits of what PV to use for each LV, you should just let it go ahead and make it's own decisions. The man page describes options where you can control stuff - like striping and mirroring. I find this just confuses the issue though and makes stuff needlessly complex. A much better viewpoint is you deal with your striping and performance issues at a lower layer - RAID - and treat LVM as something that creates a gigantic storage bucket where you take out how much you need and don't care where it is. If two drives have vastly different performance characteristics and you find yourself having to dictate to LVM what to do, then they really should not be in the same VG at all. -- alan dot mckinnon at gmail dot com