From owner-freebsd-fs Fri Jan 17 18:21:39 2003 Delivered-To: freebsd-fs@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 9E3D737B401 for ; Fri, 17 Jan 2003 18:21:38 -0800 (PST) Received: from mail.eecs.harvard.edu (bowser.eecs.harvard.edu [140.247.60.24]) by mx1.FreeBSD.org (Postfix) with ESMTP id EA04243F18 for ; Fri, 17 Jan 2003 18:21:34 -0800 (PST) (envelope-from ellard@eecs.harvard.edu) Received: by mail.eecs.harvard.edu (Postfix, from userid 465) id EBE3E54C441; Fri, 17 Jan 2003 21:21:28 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by mail.eecs.harvard.edu (Postfix) with ESMTP id E9D6054C440; Fri, 17 Jan 2003 21:21:28 -0500 (EST) Date: Fri, 17 Jan 2003 21:21:28 -0500 (EST) From: Dan Ellard To: Cheen Liao Cc: freebsd-fs@freebsd.org Subject: Re: Transaction File System - a replacement of JFS In-Reply-To: <001401c2be93$c36c7490$681adf3d@homexp> Message-ID: References: <20030114192634.75751.qmail@web13505.mail.yahoo.com> <20030117075118.GA3493@HAL9000.homeunix.com> <3E27DA7F.D5DBEFB@mindspring.com> <20030117222410.GA5449@HAL9000.homeunix.com> <001401c2be93$c36c7490$681adf3d@homexp> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On Sat, 18 Jan 2003, Cheen Liao wrote: > Recently there are discussions on JFS on FreeBSD. I think my company's > development plan may meet the demands. > > My company is planning to build a Transactional File System (TFS) on > FreeBSD, which has journaling (logging) capability and database capability. > The basic idea is to build a file system on a database engine. When it is > done, it should supersede JFS with its database functionality. > ... You should get in contact with Lex Stein (stein@eecs.harvard.edu) and Mike Tucker (mtucker@eecs.harvard.edu). They have built a file system on top of Berkeley DB, and it's completely transaction-oriented. It's open source and available to download now. The basic idea sounds like almost exactly what you're planning to do, except that it's based on Berkeley DB instead of Postgres, and its interface is a user-level NFSv3 server instead of VFS. (I don't know whether they've thought about the niftier features like snapshots/replication, beyond what is already provided by BDB) Even if you don't like exactly what they've done, and really want to use VFS, I think you'll find it much easier to cram BDB into the kernel than Postgres! If you're determined to stick with Postgres, however, you should check out Michael Olson's work on the "Inversion" file system, which used Postgres as the basis for a file system that did some of the things you are thinking about, circa 1993. (But note that following in Michael Olson's footsteps will also lead you back to Berkeley DB...) -Dan To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message