Re: journaling filesystem

Theodore Y. Ts'o (tytso@MIT.EDU)
Wed, 11 Jun 1997 16:43:37 -0400


Date: Wed, 11 Jun 1997 14:16:15 +0800 (GMT)
From: Orlando Andico <orly@gibson.eee.upd.edu.ph>

i just read about the veritas filesystem (well, yeah, it existed a long
time ago..) and was wondering if journaling is ever going to be added to
ext2fs. what must be added/modified to the driver code to support an
intent log? i think basic journaling code would "only" require addition of
an intent log (where?) and add reading of this log to e2fsck..

Adding journalling isn't so simple. One, you need ordered writes, which
is something the low-level block device interface doesn't provide.
Secondly, you have to worry about performance, which is hard to do while
still having the ordering semantics.

- Ted