From owner-freebsd-scsi@freebsd.org Tue Nov 17 08:08:08 2015 Return-Path: Delivered-To: freebsd-scsi@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 5A0F8A319F4; Tue, 17 Nov 2015 08:08:08 +0000 (UTC) (envelope-from hausen@punkt.de) Received: from kagate.punkt.de (kagate.punkt.de [217.29.33.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id C6CAA1051; Tue, 17 Nov 2015 08:08:07 +0000 (UTC) (envelope-from hausen@punkt.de) Received: from hugo10.ka.punkt.de (hugo10.ka.punkt.de [217.29.44.10]) by gate2.intern.punkt.de with ESMTP id tAH87v6K076985; Tue, 17 Nov 2015 09:07:57 +0100 (CET) Received: from [217.29.44.157] ([217.29.44.157]) by hugo10.ka.punkt.de (8.14.2/8.14.2) with ESMTP id tAH87vtO031155; Tue, 17 Nov 2015 09:07:57 +0100 (CET) (envelope-from hausen@punkt.de) Subject: ZFS on labelled partitions (was: Re: LSI SAS2008 mps driver preferred firmware version) Mime-Version: 1.0 (Mac OS X Mail 9.1 \(3096.5\)) Content-Type: multipart/signed; boundary="Apple-Mail=_1B2B703B-9A6A-4088-B7E0-8CC3E339EA61"; protocol="application/pgp-signature"; micalg=pgp-sha512 X-Pgp-Agent: GPGMail 2.6b2 From: "Patrick M. Hausen" In-Reply-To: Date: Tue, 17 Nov 2015 09:08:12 +0100 Cc: freebsd-stable , freebsd-scsi@freebsd.org Message-Id: <878D84A9-4553-413B-ACA4-5ABF499F28C1@punkt.de> References: <5644FF09.9090200@free.de> <56472686.5030301@free.de> <20151114143104.GA41119@in-addr.com> <7710CBCC-E68F-4454-9E29-E50ED1C6B511@sarenet.es> <20151116205734.GM48728@zxy.spb.ru> To: Freddie Cash X-Mailer: Apple Mail (2.3096.5) X-BeenThere: freebsd-scsi@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: SCSI subsystem List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 17 Nov 2015 08:08:08 -0000 --Apple-Mail=_1B2B703B-9A6A-4088-B7E0-8CC3E339EA61 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 Hi, all, > Am 16.11.2015 um 22:19 schrieb Freddie Cash : >=20 > =E2=80=8BYou label the disks as they are added to the system the first = time. That > way, you always know where each disk is located, and you only deal = with the > labels. we do the same for obvious reasons. But I always wonder about the = possible downsides, because ZFS documentation explicitly states: ZFS operates on raw devices, so it is possible to create a = storage pool comprised of logical volumes, either software or hardware. This configuration is not = recommended, as ZFS works best when it uses raw physical devices. Using logical volumes = might sacrifice performance, reliability, or both, and should be avoided. (from http://docs.oracle.com/cd/E19253-01/819-5461/gbcik/index.html) Can anyone shed some lght on why not using raw devices might sacrifice performance or reliability? Or is this just outdated folklore? Thanks, Patrick -- punkt.de GmbH * Kaiserallee 13a * 76133 Karlsruhe Tel. 0721 9109 0 * Fax 0721 9109 100 info@punkt.de http://www.punkt.de Gf: J=C3=BCrgen Egeling AG Mannheim 108285 --Apple-Mail=_1B2B703B-9A6A-4088-B7E0-8CC3E339EA61 Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc Content-Description: Message signed with OpenPGP using GPGMail -----BEGIN PGP SIGNATURE----- Comment: GPGTools - https://gpgtools.org iQEcBAEBCgAGBQJWSuBsAAoJEJBvLuLt2olcScMH/1VvysKjTcZqVOIltP1FyZWn LzaS3uGKVPNJKYKmL6fl0oluynUhFdupvPqLT8qI5ViMe6lpA6ay9dCZ2uhdcOhS mu2qT8orRTSNWr4DZmpuH0lxulYypEcBGN0oxwokcTuv3imVE1iMSBFnUoNWS1NT cf/jBREsixk3YFr2Az7cKG80Jcnp/T2sPrTMQV1UWvkz4qe1JEUCU5VflUhPEH56 CJpp5U1647nrlvqmsv5XZgENtA3QGN2WrhFei56C1wGRkrmqDGy81WQzQAaVsPbD t6JgaOJaFKB+m4S1T3Ar0Qf96rp6/mm+/f96fCaurzK4oBuHSuuaJPs5cHUPke4= =MTIy -----END PGP SIGNATURE----- --Apple-Mail=_1B2B703B-9A6A-4088-B7E0-8CC3E339EA61--