From owner-freebsd-hackers Tue May 22 6:32:52 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from smtpproxy1.mitre.org (mb-20-100.mitre.org [129.83.20.100]) by hub.freebsd.org (Postfix) with ESMTP id 2C4AA37B422 for ; Tue, 22 May 2001 06:32:48 -0700 (PDT) (envelope-from jandrese@mitre.org) Received: from avsrv1.mitre.org (avsrv1.mitre.org [129.83.20.58]) by smtpproxy1.mitre.org (8.9.3/8.9.3) with ESMTP id JAA10286; Tue, 22 May 2001 09:31:37 -0400 (EDT) Received: from MAILHUB1 (mailhub1.mitre.org [129.83.20.31]) by smtpsrv1.mitre.org (8.9.3/8.9.3) with ESMTP id JAA19190; Tue, 22 May 2001 09:31:36 -0400 (EDT) Received: from dhcp-105-164.mitre.org (128.29.105.164) by mailhub1.mitre.org with SMTP id 6554965; Tue, 22 May 2001 09:31:24 -0400 Message-ID: <3B0A6A36.5E8EF98C@mitre.org> Date: Tue, 22 May 2001 09:31:34 -0400 From: Jason Andresen Organization: The MITRE Corporation X-Mailer: Mozilla 4.75 [en]C-20000818M (Windows NT 5.0; U) X-Accept-Language: en MIME-Version: 1.0 To: "Albert D. Cahalan" Cc: ccf@master.ndi.net, gordont@bluemtn.net, jkh@osd.bsdi.com, freebsd-hackers@freebsd.org Subject: Re: technical comparison References: <200105220411.f4M4BDX101825@saturn.cs.uml.edu> 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 "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 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). Heck, the system didn't even try to boot when it came back, I had to pull out the rescue disk and run fsck from there. Good thing the rescue disk was the same as the install disk, it saved me a disk swap. :( If only FreeBSD could boot from those funky M-Systems flash disks. > So, no async here, and "UFS + soft updates" can't touch the > performance on huge directories. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message