From owner-freebsd-questions@FreeBSD.ORG Sat Apr 19 21:27:13 2008 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 55BC610656C9 for ; Sat, 19 Apr 2008 21:27:13 +0000 (UTC) (envelope-from freebsd-questions@m.gmane.org) Received: from ciao.gmane.org (main.gmane.org [80.91.229.2]) by mx1.freebsd.org (Postfix) with ESMTP id D407B8FC14 for ; Sat, 19 Apr 2008 21:27:12 +0000 (UTC) (envelope-from freebsd-questions@m.gmane.org) Received: from list by ciao.gmane.org with local (Exim 4.43) id 1JnKaQ-0004Lf-Vt for freebsd-questions@freebsd.org; Sat, 19 Apr 2008 21:27:06 +0000 Received: from 89-172-44-123.adsl.net.t-com.hr ([89.172.44.123]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sat, 19 Apr 2008 21:27:06 +0000 Received: from ivoras by 89-172-44-123.adsl.net.t-com.hr with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sat, 19 Apr 2008 21:27:06 +0000 X-Injected-Via-Gmane: http://gmane.org/ To: freebsd-questions@freebsd.org From: Ivan Voras Date: Sat, 19 Apr 2008 23:26:57 +0200 Lines: 57 Message-ID: References: <20080419172100.GA3638@lastamericanempire.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigDE19D8B57EF73FC1DF85C3E9" X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: 89-172-44-123.adsl.net.t-com.hr User-Agent: Thunderbird 2.0.0.12 (Windows/20080213) In-Reply-To: <20080419172100.GA3638@lastamericanempire.com> X-Enigmail-Version: 0.95.6 Sender: news Subject: Re: gmirror, geli, gjournal performance X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 19 Apr 2008 21:27:13 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigDE19D8B57EF73FC1DF85C3E9 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable hideo wrote: > Hi everyone, >=20 > I was replacing a disk in a gmirror+geli pair and decided to compare > the performance of gmirror+geli+gjournal before adding the new disk. >=20 > When using these three together is the appropriate order to 1) fdisk > and label 2) mirror the disk, 3) geli the partitions, and 4) use the > geli partitions for gjournal label? It depends on what you want to do. To minimize administration overhead=20 I'd modify the sequence like this: gmirror the drives, geli the entire=20 gmirror, then fdisk it, then add gjournal, use UFS labels. Of course,=20 you can never boot from such a thing. > With respect to performance, I find the writes to the gjournal disk > about half as fast, which I expected from the benchmarks I've seen. > However, reading a single file is identical between the two: >=20 > dd if=3D/sofupdates/1.mpg of=3D/dev/null bs=3D1m > 994049168 bytes transferred in 34.858793 secs (28516454 bytes/s= ec) >=20 > dd if=3D/gjournal/1.mpg of=3D/dev/null bs=3D1m > 994049168 bytes transferred in 34.335267 secs (28951258 bytes/s= ec) >=20 > Is this expected? I was under the impression that reads should be > somewhat faster with gjournal. Is geli decryption the limiting > factor here? No, performance with gjournal can at most be as fast as without gjournal = (in reality it will always be infinitesimally slower since there's=20 another layer in GEOM added). --------------enigDE19D8B57EF73FC1DF85C3E9 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.5 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFICmOhldnAQVacBcgRAnu2AJ4qhUZWpmZycr4Bx/6qv/6Q+ppu/QCgl934 ENqvmqTpnMvZjssJcP6hWYg= =AJvG -----END PGP SIGNATURE----- --------------enigDE19D8B57EF73FC1DF85C3E9--