From owner-freebsd-fs Thu Aug 19 8:47: 1 1999 Delivered-To: freebsd-fs@freebsd.org Received: from gatewaya.anheuser-busch.com (gatewaya.anheuser-busch.com [151.145.250.252]) by hub.freebsd.org (Postfix) with SMTP id 06922150B0; Thu, 19 Aug 1999 08:46:42 -0700 (PDT) (envelope-from Matthew.Alton@anheuser-busch.com) Received: by gatewaya.anheuser-busch.com; id KAA02280; Thu, 19 Aug 1999 10:47:29 -0500 Received: from stlexggtw002-pozzoli.fw-users.busch.com(151.145.101.130) by gatewaya.anheuser-busch.com via smap (V5.0) id xma002157; Thu, 19 Aug 99 10:46:42 -0500 Received: from stlabcexg006.anheuser-busch.com ([151.145.101.161]) by 151.145.101.130 (Norton AntiVirus for Internet Email Gateways 1.0) ; Thu, 19 Aug 1999 15:44:28 0000 (GMT) Received: by stlabcexg006.anheuser-busch.com with Internet Mail Service (5.5.2448.0) id ; Thu, 19 Aug 1999 10:44:06 -0500 Message-ID: <0740CBD1D149D31193EB0008C7C56836EB8B14@STLABCEXG012> From: "Alton, Matthew" To: "'Russell Cattelan'" Cc: "'Hackers@FreeBSD.ORG'" , "'fs@FreeBSD.ORG'" Subject: RE: BSD XFS Port & BSD VFS Rewrite Date: Thu, 19 Aug 1999 10:44:27 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2448.0) Content-Type: text/plain; charset="iso-8859-1" Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Do you have access to more of the code than is currently posted on SGI's web page? I am willing to sign an NDA in order to get access to all relevant source. I would like to assist in porting XFS to Linux also. I would very much like to see SGI succeed by using open source software in the commercial realm. As for licensing issues, I am purely agnostic -- I trust that any legal issues can be worked out after the fact by the proper people. > -----Original Message----- > From: Russell Cattelan [SMTP:cattelan@thebarn.com] > Sent: Thursday, August 19, 1999 12:41 AM > To: Alton, Matthew > Cc: 'Hackers@FreeBSD.ORG'; 'fs@FreeBSD.ORG' > Subject: Re: BSD XFS Port & BSD VFS Rewrite > > Glad to hear somebody is willing to dive in to XFS. > > > Right now I am one of three people working on the XFS to linux port, so I > have > pretty good view of what is currently happening. > > When is it going to be ready? > Don't hold your breath. Officially SGI has said by the end of the year, > technically... whew > frankly I can't even guess. I would hope within a month or so we will > have the basics of a FS. > > There are a lot of hurtles to overcome. XFS is a very very complex file > system that relies on > some of the more advanced features of IRIX. The buffer cache and chunk > cache (chunking > buffers together to do large IO) are two examples that come to mind. SGI > is rewriting > the buffer cache (calling it the page cache) such that is will be able to > support XFS. > chunk cache... ? not sure what we are going to do with that. > > We have been having several discussions about the best way to > "interface". > IRIX uses VFS,VNODE,BEHAVIOR which is similar to the BSD's interface > but of course very IRIX specific. Linux's vfs/vnode is different from > either. > Realizing this, a lot of our discussions have been around how to go at > making a > new/modify existing interface layer that might be more "universal" > i.e. not irix not linux not bsd not etc.... specific. > > In reading Terry's & Bill's comments seems there is a a lot of room for > improvement. > > Initially we trying to make as few changes as possible to XFS to get an > initial implementation > running on linux. After we get things running we will start to analyze > where the problems exist, > and decide what direction in terms of interface to take at that time. > > I would like any constructive input people have on this matter. I have a > pretty good > chance of setting design direction. > Be waned: SGI at the moment is committed to linux, development directions > will favor that platform. > They are not against other OS's being XFS'atized but SGI is in the > business of selling > hardware/solutions based on that hardware and linux one of the OS they > have decided to use for > their intel based boxes. > > Also as far as the GPL issue goes, get over it! I understand the issues > and agree with many > of the points. > My suggestion lets find a way to work with the GPL (i.e. loadable kernel > module / > softupdates model) > If somebody has a very very good argument/solution to the licensing > debate let me > know, I can present it to the people dealing with the lawyers. > The license issue has slowed the release of the actual code more than > anything else, > and will not be revisited again without great pain. > > > > I am currently conducting a thorough study of the VFS subsystem > > in preparation for an all-out effort to port SGI's XFS filesystem to > > FreeBSD 4.x at such time as SGI gives up the code. Matt Dillon > > has written in hackers- that the VFS subsystem is presently not > > well understood by any of the active kernel code contributers and > > that it will be rewritten later this year. This is obviously of great > > concern to me in this port. I greatly appreciate all assistance in > > answering the following questions: > > > > 1) What are the perceived problems with the current VFS? > > 2) What options are available to us as remedies? > > 3) To what extent will existing FS code require revision in order > > to be useful after the rewrite? > > 4) Will Chapters 6,7,8 & 9 of "The Design and Implementation of > > the 4.4BSD Operating System" still pertain after the rewrite? > > 5) How important are questions 3 & 4 in the design of the new > > VFS? > > > > I believe that the VFS is conceptually sound and that the existing > > semantics should be strictly retained in the new code. Any new > > functionality should be added in the form of entirely new kernel > > routines and system calls, or possibly by such means as > > converting the existing routines to the vararg format &etc. > > > > Does anyone know when SGI will release XFS? > > > > > > -- > Russell Cattelan > cattelan@thebarn.com > > > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-hackers" in the body of the message To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message