From owner-freebsd-stable@FreeBSD.ORG Fri Mar 28 15:26:30 2008 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 5695C106566B for ; Fri, 28 Mar 2008 15:26:30 +0000 (UTC) (envelope-from freebsd-stable@m.gmane.org) Received: from ciao.gmane.org (main.gmane.org [80.91.229.2]) by mx1.freebsd.org (Postfix) with ESMTP id CC1298FC1D for ; Fri, 28 Mar 2008 15:26:29 +0000 (UTC) (envelope-from freebsd-stable@m.gmane.org) Received: from list by ciao.gmane.org with local (Exim 4.43) id 1JfGTI-00031A-Oj for freebsd-stable@freebsd.org; Fri, 28 Mar 2008 15:26:24 +0000 Received: from lara.cc.fer.hr ([161.53.72.113]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 28 Mar 2008 15:26:24 +0000 Received: from ivoras by lara.cc.fer.hr with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 28 Mar 2008 15:26:24 +0000 X-Injected-Via-Gmane: http://gmane.org/ To: freebsd-stable@freebsd.org From: Ivan Voras Date: Fri, 28 Mar 2008 16:26:16 +0100 Lines: 60 Message-ID: References: <47EBA3AB.40307@infracaninophile.co.uk> <200803280029.08136.danny@ricin.com> <20080328142843.GD28690@dan.emsphone.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig7910809D3E036755CF293A1D" X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: lara.cc.fer.hr User-Agent: Thunderbird 2.0.0.6 (X11/20071022) In-Reply-To: <20080328142843.GD28690@dan.emsphone.com> X-Enigmail-Version: 0.95.0 Sender: news Subject: Re: Question about file system checks 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: Fri, 28 Mar 2008 15:26:30 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig7910809D3E036755CF293A1D Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Dan Nelson wrote: > In the last episode (Mar 28), Ivan Voras said: > Note that you can tweak the SU caching time by adjusting the sysctls > kern.{meta,dir,file}delay. Take them down to 10 seconds instead of 30 > and you'll lose less files (at the cost of more disk I/O of course). Yes, but the other file systems were also tested with their respective defaults. >> 5. ZFS on FreeBSD was the fastest, in the sense of creating the most f= iles=20 >> during this benchmark (though speed was not the target for this benchm= ark=20 >> so this is a low-quality observation), closely followed by JFS and XFS= =2E >=20 > ZFS's transaction commit interval is only 5 seconds (see txg_time in > uts/common/fs/zfs/txg.c); how many more files/second did it create vs > the others to be able to lose the most files in that window? :) All were tested within the same time: 50 seconds. Details: the machine being tested was connected to a "reporter" machine via plain crossover cable, the reporter had a TCP server and the tested machine had a TCP client that run a tight loop of IO operations, single threaded, randomly choosing between creating files and directories, appending to them and changing (a random amount of data in a random position) them, then sending to the server a description (log) of each IO operation after it has been done. These were several Python scripts I wrote. After 50 seconds I'd pull the plug off the server (meaning it's not *exactly* 50 seconds but 50 seconds+time of my action, but it doesn't matter as everything is timestamped), plug it back in, run fsck. The reporting server would replay the log of IO operations from the first to the last and generate a report of what should have been on the tested machine which would then be compared with what was found on the tested machine (by scripts/automated). --------------enig7910809D3E036755CF293A1D Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQFH7Q4YldnAQVacBcgRAo3TAKCtKLUE5VeftLm1dP5zxD50+ro8/ACgrMIS 03T1I5fsIVcVnfnpL/d5bxo= =FfHf -----END PGP SIGNATURE----- --------------enig7910809D3E036755CF293A1D--