Re: Corrupted/unreadable journal: reiser vs. ext3

[Dirk Schenkewitz <Dirk.Schenkewitz@interface-ag.com>]

Wayne,

berthiaume_wayne@emc.com schrieb:
> 
>      Dirk, I'd be interested in hearing from you your performance
> experience with ext3 when it reaches 96% full.

Well (*shrug*), there seems to be nothing special about it. I did
not do any timing test when such a fileysytem went full. In fact,
becoming 100% full is not "mormal", it happens when I put stuff
on it just to have it out of the way for some time. The filesystem
is then used as some kind of "storage cellar".

Aside from that - speed becomes noticeable (I believe, at least)
when using 'xv' on a directory with lots of pictures, say, between
2000 and 3000, and the thumbnails are loaded during the first access.
This takes more than a minute (estimated, I did not look at the
clock).

Another thing is when 'xv' creates the thumbnails. A few times it
happened that a filesystem which was rather full ran out of space
when creating the thumbnails. (That's not critical, all you "loose"
are some of the thumbnails, which can be recreated any time later.)
But I don't know how/when 'xv' stores the thumbnails, I only know 
that they are kept in memory as long as they are in use. Then linux
itself does some buffering, so only the first access on a directory
can make a testimony. That said, I can can only talk of my subjec-
tive impressions, and I have not noticed any slowdown until there
are 0 bytes left. But it is hard to tell, because the difference
between 96% and 100% are only 320 MB on a 8 GB partition, and that
space fills up rather fast.

While you ask - what are the "amounts" of slowdown if a reiserfs
gets more than 96% full? 
 - Less than 4% percent? (I might not notice that.)
 - between 4% and 8%? (I might notice, but I can live with that
   easily. Then again, ext3 doesn't seem to have such problems.)
 - more than 8%, maybe much more? (That might become annoying.
   In that case I believe that ext3 is better for my purposes.)

You see, I'm not an expert, I'm "just using filesystems". Please
take the mentioned percentages as guesses - depending on the
situation, I might not even notice 10% slowdown...

Hope that answers your question - does it?

Happy coding
	dirk
-- 
Dirk Schenkewitz 

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