As i know, journal file systems and journal services are completly
different.

A journal file systems works with his filesystems like a database, put the
changes in a log, make the changes and if succesfull, delete the record from
the log. If the OS crashes during a write action, your filesystem can
survive.

The journal service makes a list of the files that are changed. So, if you
do a backup, it looks into the list and does a backup of that files. The
client don't needs to check the whole filesystem anymore to see which files
are changed. If you have a NT of W2k fileserver with over a million files,
the backuptime could be down from jl. 4 hours to an half hour.

Greetings,
   Maurice van 't Loo
   Compare Computers
   The Netherlands