DOH! ata_alloc_composite failed!

[Jan Catrysse]

Dear subscribers,

I am currently running a production server:
FreeBSD 6.2 STABLE
Onboard Intel ICH8R Raid 1 with 2x SATA300 500GB HDD
Using ATA for Raid1

In my today's /var/log/messages I found:
Nov 22 03:01:33 www kernel: DOH! ata_alloc_composite failed!
Nov 22 03:01:33 www last message repeated 28 times

I've seen several topics on similar problems but without resolution.
Other users have seen the problem when there is heavy I/O, the UID check
done by one of the Periodic/Security scripts has been mentioned. Not
impossible because the error occurs around 03:00 hours, when
Periodic/Daily is ran.

Someone has a clew on what this could be?
Should I be worrying for my data?
How can I do some more diagnostics without putting the server down (if
possible)?
Please see my next post / question on Raid Synchronisation / Data
Consistency.

Kind regards,
Jan Catrysse