From owner-freebsd-hackers Tue May 22 11:16:40 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from saturn.cs.uml.edu (saturn.cs.uml.edu [129.63.8.2]) by hub.freebsd.org (Postfix) with ESMTP id D5AE737B424 for ; Tue, 22 May 2001 11:16:34 -0700 (PDT) (envelope-from acahalan@saturn.cs.uml.edu) Received: (from acahalan@localhost) by saturn.cs.uml.edu (8.11.0/8.11.2) id f4MIGK1171051; Tue, 22 May 2001 14:16:20 -0400 (EDT) From: "Albert D. Cahalan" Message-Id: <200105221816.f4MIGK1171051@saturn.cs.uml.edu> Subject: Re: technical comparison To: jandrese@mitre.org (Jason Andresen) Date: Tue, 22 May 2001 14:16:20 -0400 (EDT) Cc: acahalan@cs.uml.edu (Albert D. Cahalan), ccf@master.ndi.net, gordont@bluemtn.net, jkh@osd.bsdi.com, freebsd-hackers@freebsd.org In-Reply-To: <3B0A6A36.5E8EF98C@mitre.org> from "Jason Andresen" at May 22, 2001 09:31:34 AM X-Mailer: ELM [version 2.5 PL2] MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Jason Andresen writes: > "Albert D. Cahalan" wrote: >> It should be immediately obvious that ext2 is NOT the filesystem >> being proposed, async or not. For large directories, ext2 sucks >> as bad as UFS does. This is because ext2 is a UFS clone. >> >> The proposed filesystem is most likely Reiserfs. This is a true >> journalling filesystem with a radically non-traditional layout. >> It is no problem to put millions of files in a single directory. >> (actually, the all-in-one approach performs better than a tree) >> >> XFS and JFS are similarly capable, but Reiserfs is well tested >> and part of the official Linux kernel. You can get the Reiserfs >> team to support you too, in case you want to bypass the normal >> filesystem interface for even better performance. > > Er, I don't think ReiserFS is in the Linux kernel yet, although it is > the default filesystem on some distros apparently. I think Linus has > some reservations about the stability of the filesystem since it is It is in the kernel: http://lxr.linux.no/source/fs/reiserfs/?v=2.4.4 Bugs died left and right when it went in. > fairly new. That said, it would be hard to be much worse than Ext2fs > with write cacheing enabled (default!) in the event of power failure. > We only have three Linux boxes here (and one is a PC104 with a flash > disk) and already I've had to reinstall the entire OS once when we had a > power glitch. ext2fsck managed to destroy about 1/3 of the files on the > system, in a pretty much random manner (the lib and etc were hit hard). If you don't like ext2, why should it like you? :-) I power cycle a Linux box nearly every day to reset a board. > If only FreeBSD could boot from those funky M-Systems flash disks. If you want flash, use a filesystem designed for flash. (not UFS, ext2, Reiserfs, XFS, JFS, or FAT... try JFFS2) >> So, no async here, and "UFS + soft updates" can't touch the >> performance on huge directories. From another email you mention benchmarking with: > Linux 2.2.16 with ext2fs and write caching > 10000 transactions, 60000 simultanious files: 1. The 2.2.16 kernel is obsolete. 2. 60000 files is not a lot. Try a few million files. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message