[mythtv] Which filesystem?

[Poul Petersen]

> What I noticed was that the overhead for journalling on ext3 with
> a quasi-realtime task (vcr/myth) using a low-latency/preemption patched
> kernel (using a AMD Athlon 2100XP, Symbios LVD scsi controller on to
> a U2W 47mb/s Hitachi 10,000rpm drive) was causing drops due to writer task
> not flushing frames fast enough.  But by changing to ext2 for the 
> partition that the captures goto, I stopped having frame drops.
> 
> (kernel RH 7.3 2.4.18-5 + preemption+low-latency )
> 
> I've also tried it on ide with the later ide patches with much the 
> same results.
> 
> My normal mount options were for ext3 = noatime,data=writeback
> My normal mount options for ext2 = noatime

	There have been quite a few errata updates for RH 7.3 - I think
they are upto 2.4.18-19 or something like that. I also recall seeing
mention of a sync problem with ext3 on the ext3 mailing list perhaps
5 months ago - the problem would cause a very brief "hang" every three
minutes or so, probably enough to cause a few frames to drop. I don't know
if RedHat has included the patches for this that were posted on the
ext3 mailing list - have a look at the thread at:

http://www.redhat.com/mailing-lists/ext3-users/msg03635.html

	I am one of the few that had terrible experiences with XFS.
We have had XFS running on several machines, but the one we had the
most trouble with was a NFS server - we tried for six months with the
help of the XFS group to get the problems resolved, but our system
would bomb every 10 days even after switching to completely different
hardware. On the other hand, our backup server has been running XFS
for 2 years without a single problem. We switched the NFS server to
ext3 and it has been up for 213 days. As usual, YMMV.

-poul