The smp kernel does not address memory above 16 GB. If you have more memory (16 - 64 GB) use the hugemem kernel, if not there is no reason, that I know of, to use it. We are also running on the 2.4.21-32.0.1 kernel without any problems on RHEL 3. I am not familiar with OCFS. I'm running ext3. On a side note, I would strongly suggest that you use hugetlb since I saw huge performance gains implementing that. -- Magnus Andersen Systems Administrator / Oracle DBA Walker & Associates, Inc.