[ILUG] Linux Myths. The truth can be told!

[Raymond Kelly]

I presume that the intention was to send this to the list.
Thanks for the info, it definately makes some sense now.

regards
	Ray ...

-------- Original Message --------
Subject: Re: [ILUG] Linux Myths. The truth can be told!
Date: Wed, 6 Oct 1999 12:47:06 GMT
From: Niall  O Broin <nobroin at sced.esoc.esa.de>
To: ray at phbrink.ie

Raymond Kelly asked  

> Just a quick question from the ignorant ..
> What is the difference between a Journaling & non-journaling FS

Anywhere from two minutes to an hour depending on the size of your
filesystem :-)


Oh, ok, as you're ignorant . . . .

A journalling filesystem logs (or rather journals) all changes to the
filesystem
in a special file. The advantage of this is that when it's necessary to
fsck the
filesystem e.g. after an unclean shutdown due to a power outage the
journal makes
this very much faster. I have a 16GB ext2fs filesystem which takes >10
minutes to
fsck after an unclean shutdown. In fairness, it doesn't happen very
often, but it's
a pain in the neck when it does. 

Now don't anybody please bitch about the above - it's a 5 line precis
for the ignorant.
I know about journalling all data / only metadata etc. - I've Tweedie's
paper on the
desk beside me and I've read Reiser's stuff, and there's whatever's
coming from SGI.

Kindest regards,


Niall  O Broin		

UNIX Network Administrator 		 	nobroin at esoc.esa.de
Ground Systems Engineering Department		Ph./Fax  +49 6151 90 3619/2179
European Space Operations Centre, Darmstadt, Germany