Thanks for the reply. That would be the problem I think. It's the stock centos 5.5 kernel. I have enough space externally to copy all of the data off. I'm thinking of doing that, deleting the raid 5 setup, and creating a raid 6 setup from scrath given the high number of events in the array. It will also allow me to use a more recent metadata format. What do you think and if I do that do I still need to upgrade my kernel? Thanks.
# uname -a
Linux lexicon 2.6.18-194.el5 #1 SMP Fri Apr 2 14:58:14 EDT 2010 x86_64 x86_64 x86_64 GNU/Linux