Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 29 Jan 2000 17:54:03 -0800 (PST)
From:      Tom <tom@uniserve.com>
To:        Cy Schubert - ITSD Open Systems Group <Cy.Schubert@uumail.gov.bc.ca>
Cc:        Kris Kennaway <kris@hub.freebsd.org>, Ataualpa Albert Carmo Braga <atabraga@iqm.unicamp.br>, freebsd-stable@FreeBSD.ORG
Subject:   Re: JFS 
Message-ID:  <Pine.BSF.4.05.10001291747520.8409-100000@shell.uniserve.ca>
In-Reply-To: <200001300024.QAA03100@cwsys.cwsent.com>

next in thread | previous in thread | raw e-mail | index | archive | help
On Sat, 29 Jan 2000, Cy Schubert - ITSD Open Systems Group wrote:

> In message <Pine.BSF.4.21.0001291419200.81350-100000@hub.freebsd.org>, 
> 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




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.BSF.4.05.10001291747520.8409-100000>