From owner-freebsd-stable Sat Jan 29 17:54:18 2000 Delivered-To: freebsd-stable@freebsd.org Received: from mail2.uniserve.com (members.uniserve.ca [204.244.156.7]) by hub.freebsd.org (Postfix) with ESMTP id 272BC1509E; Sat, 29 Jan 2000 17:54:13 -0800 (PST) (envelope-from tom@uniserve.com) Received: from shell.uniserve.ca ([204.244.186.218]) by mail2.uniserve.com with esmtp (Exim 3.13 #1) id 12EjZ1-00048T-00; Sat, 29 Jan 2000 17:54:07 -0800 Date: Sat, 29 Jan 2000 17:54:03 -0800 (PST) From: Tom X-Sender: tom@shell.uniserve.ca To: Cy Schubert - ITSD Open Systems Group Cc: Kris Kennaway , Ataualpa Albert Carmo Braga , freebsd-stable@FreeBSD.ORG Subject: Re: JFS In-Reply-To: <200001300024.QAA03100@cwsys.cwsent.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Sat, 29 Jan 2000, Cy Schubert - ITSD Open Systems Group wrote: > In message , > Kris Ken > naway writes: > > On Fri, 28 Jan 2000, Ataualpa Albert Carmo Braga wrote: > > > > > Is there something like JFS (AIX) in FreeBSD ? > > > > Please consult the mailing-list archives. > > 4.4BSD has something like JFS, LFS (Log Structured Filesystem). LFS > developed from a paper by John Ousterhout, the same fellow who > developed Tcl & Tk. All other log structured filesystems, JFS, AdvFS, > Veritas Filesystem, are based on Ousterhout's work. > > Due to the lack of interest, FreeBSD's LFS has fallen into disrepair > over the years. With the implementation of softupdates in FreeBSD I > don't think there is any need for LFS any more. LFS is _VERY_ different from JFS, AdvFS, Vertias, et al. In LFS, the entire filesystem is a log. A typical journalled filesystem, just has a small journal area for metainformation updates. There is a huge difference. Journalling is going to be requirement. The reason why everyone wants a journalled filesystem, is for fast fsckes. Softupdates does not do that yet, but it is apparently in development. Softupdates a lot of the intelligent metadata update re-ordering stuff that is used by a lot of journalled filesystems. I think the idea is to add a journal to softupdates. Sun has done something like this with their UFS, which can operate in journalled and non-journalled mode. > Regards, Phone: (250)387-8437 > Cy Schubert Fax: (250)387-5766 > Sun/DEC Team, UNIX Group Internet: Cy.Schubert@uumail.gov.bc.ca > ITSD > Province of BC > "COBOL IS A WASTE OF CARDS." > Tom Uniserve To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message