[plug] NAS (RAID EXT4) directory listing issues

[Tim]

I've recently purchased a NAS to hold my increase volume of data, and
to give me some piece of mind with my photo storage. I have a 4 bay
QNAP, with 3 1TB drive in RAID 5. I formatted it ext4 due to the fact
that from what I could read, it's a much better file system and should
be faster, especially for large files like digital video files.
Unfortunately, it's now playing up. On certain folders, that contain
20-40 sub folders which contain large video files, it freezes so to
say. Attempting to get a directory listing will timeout (if via
network shares) or just freeze if locally. Running strace reveals it's
stopped on a getdents64 call which I believe is it trying to get
directory entries.

Having not played with RAID or EXT4 before, I'm not sure which part to
blame. System load is high when this happens, but CPU usage is low. A
reboot fixes things for some time.
(For those unfamiliar with the QNAP, it's a linux based system, so the
RAID is linux RAID).

Any hints? Should I find some way to downgrade to EXT3 and see if that
helps? Are files systems > 1TB too much for this low end QNAP (800Mhz
ARM processor)?

Any pointers would be great.

Thanks

Tim

-- 
Timothy White - Somewhere in Australia