From owner-freebsd-arch@FreeBSD.ORG Sat Jan 2 22:22:53 2010 Return-Path: Delivered-To: freebsd-arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 4829A1065692 for ; Sat, 2 Jan 2010 22:22:53 +0000 (UTC) (envelope-from peterjeremy@acm.org) Received: from fallbackmx08.syd.optusnet.com.au (fallbackmx08.syd.optusnet.com.au [211.29.132.10]) by mx1.freebsd.org (Postfix) with ESMTP id C71038FC14 for ; Sat, 2 Jan 2010 22:22:51 +0000 (UTC) Received: from mail35.syd.optusnet.com.au (mail35.syd.optusnet.com.au [211.29.133.51]) by fallbackmx08.syd.optusnet.com.au (8.13.1/8.13.1) with ESMTP id o02L1Lmh021271 for ; Sun, 3 Jan 2010 08:01:21 +1100 Received: from server.vk2pj.dyndns.org (c122-106-232-83.belrs3.nsw.optusnet.com.au [122.106.232.83]) by mail35.syd.optusnet.com.au (8.13.1/8.13.1) with ESMTP id o02L17oY009485 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sun, 3 Jan 2010 08:01:09 +1100 X-Bogosity: Ham, spamicity=0.000000 Received: from server.vk2pj.dyndns.org (localhost.vk2pj.dyndns.org [127.0.0.1]) by server.vk2pj.dyndns.org (8.14.3/8.14.3) with ESMTP id o02L0wIj039408; Sun, 3 Jan 2010 08:00:58 +1100 (EST) (envelope-from peter@server.vk2pj.dyndns.org) Received: (from peter@localhost) by server.vk2pj.dyndns.org (8.14.3/8.14.3/Submit) id o02L0vp5039406; Sun, 3 Jan 2010 08:00:57 +1100 (EST) (envelope-from peter) Date: Sun, 3 Jan 2010 08:00:57 +1100 From: Peter Jeremy To: Pieter de Goeje Message-ID: <20100102210056.GD32012@server.vk2pj.dyndns.org> References: <61364.1262345170@critter.freebsd.dk> <201001012153.44349.pieter@degoeje.nl> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="x4pBfXISqBoDm8sr" Content-Disposition: inline In-Reply-To: <201001012153.44349.pieter@degoeje.nl> X-PGP-Key: http://members.optusnet.com.au/peterjeremy/pubkey.asc User-Agent: Mutt/1.5.20 (2009-06-14) Cc: Poul-Henning Kamp , freebsd-current@freebsd.org, freebsd-arch@freebsd.org Subject: Re: File system blocks alignment X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 02 Jan 2010 22:22:53 -0000 --x4pBfXISqBoDm8sr Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Thanks for that testing - the results are quite enlightening. Given that the PC architecture forces unaligned partition boundaries by default, these drives are likely to wind up with a bad reputation for performance. On 2010-Jan-01 21:53:43 +0100, Pieter de Goeje wrote: >- Partition size was 10GB, dump archive ~550MB (dump of /). The archive ea= sily >fitted in main memory (8GB). =2E.. >It was somewhat surprising to see restore being faster than tar in the ali= gned >case though. Mounting async or using soft updates resulted in a 6sec resto= re,=20 >while tar took about 8sec. With async or softupdates, there is likely to be virtually no physical write activity during the restore, with all the data winding up in the buffer cache to be flushed during the unmount. IMO, the 'restore' timing should include the unmount, changing: > cd /mnt > echo "restore" >> $results > time -ao $results restore -rf $fsarchive || exit 1 > cd / > umount /mnt > echo "fsck_ffs" >> $results to: > echo "restore" >> $results > time -ao $results sh -c 'cd /mnt && restore -rf $fsarchive && cd / && unm= ount /mnt' || exit 1 > echo "fsck_ffs" >> $results --=20 Peter Jeremy --x4pBfXISqBoDm8sr Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.14 (FreeBSD) iEYEARECAAYFAks/tAgACgkQ/opHv/APuIdY1wCgqCqdnZxuEidkv1lpZ5dn7vRL cDEAn2Qvq+H/kFxI2YheKWR5PWsHWvHh =+Tvm -----END PGP SIGNATURE----- --x4pBfXISqBoDm8sr--