Subject: Re: filesystem reliability
From: (Rob Warnock)
Date: Fri, 24 Oct 2003 06:22:24 -0500
Newsgroups: comp.lang.lisp,comp.os.linux.misc
Message-ID: <>
Marcin 'Qrczak' Kowalczyk  <> wrote:
| mike420 wrote:
| > If this is true, why aren't the same filesystems used under modern OSes
| > (*NIX and Windows)? AFAIK all RW filesystems on all of these OSes need to
| > be checked after crashes.
| No, filesystems with journaling don't have to be checked
| (e.g. ext3, xfs, reiserfs).

This is not quite true: journaling filesystems *DO* have to be
processed after a crash -- to finish writes which were journaled
but not yet committed to file space. E.g., XFS filesystems need
to run "xfs_recover" when the system reboots.

What *is* true is that this process is typically several orders of
magnitude faster than "fsck" on old-style filesystems, since only
the portion of the log written since the last full sync needs to be
processed, and the size of that is dependent only on the write rate
at the time of the crash and (unlike old-style filesystems) *not* upon
the total size of the filesystem or its occupancy.


Rob Warnock			<>
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