On Thu, 4 May 2000, Brook humphrey wrote:
> It is a journeling file system. When your system crashes it can recover
> faster without having to use fsck. Also it's supposed to be faster than
> ext2.
>
> ptah wrote:
> >
> > What are the benifits of reiserfs over ext2fs? I haven't
> > heard much about this yet. Thanks
I'm not a filesystem guru so forgive me if i get some of the terminoligy
incorrect, feel free to correct me/whatever..
reiserfs and ext2 seem about the same speed for large files, but according
to the reiserfs home page there are a few small file improvements:
- the inodes are nonexistent or done differently so you aren't limited in
the number of small files you have on a disk (for example on a large news
spool disk, with ext2 we have to create the filesystem with tons of
inodes, which cuts into usable filesystem space and it still took a couple
tries to get it right ;)
- recovery time is _way_ better than ext2 in the event of a system crash.
For example, the 11g /usr on this machine took at least 5 mins to fsck
when it was about half full. The reiserfs /usr is about the same amount
full now and takes 8-12 seconds to replay the log file.
This is extremely useful on large-scale production servers, for example a
mail or news server, where several gigabytes of data can be stored on a
single filesystem and if there is a system crash the system will be back
up in about a minute instead of having a half-hour or so of downtime.
One thing I did see on the reiserfs web site
(http://www.devlinux.com/projects/reiserfs) was a conflict with kernel
RAID and reiserfs. I havn't noticed any problems with append/RAID0 modes,
however...RAID5+reiserfs kills the raidsyncd process so the array never
refreshes (hey i was bored what else is there to do;)
Otherwise i've been using reiserfs for about 8 days have seen only 1
system problem that could possibly be related to reiserfs itself, besides
the RAID5 issue. Just 10 minutes ago, after doing mkreiserfs, mounting,
sync, umount, then mount and df, then tried to umount. The umount process
hung, so i tried sync and that hung also (other filesystems were still
responding and working properly, just the new one seemed to be "lost")
Had to shutdown/restart to get the partition back and kill the hung
"umount" and "sync" processes....after restarting after a dirty shutdown
nothing was missing.
-dwild
