Here is an interesting video of David Chinner discussing recent improvements of XFS:

http://www.youtube.com/watch?v=FegjLbCnoBw

Here is an article with related discussion including comments from Chinner:

http://lwn.net/Articles/476263/

In both the video and the article comments, Chinner states that all of the XFS improvements were incorporated into RHEL 6.2, so CentOS 6.3 should also have all of the enhancements.

I tried all of the suggestions from the LSI support pages, but I only saw a very minor improvement.

I have not found a way to disable journaling all together in XFS to see how that affects performance. If anyone knows how to do that, please let me know.

I am going to try ext4 and see how it compares to XFS for my application.