Last night, Christer and I were playing with the Ubuntu 8.04 installer, trying to break it, and get any last bugs reported before final is released tomorrow.
What I noticed last night, during the install really surprised me. ReiserFS is a screaming filesystem compared to XFS. After doing the install 3 times on 2 identical machines (Dell Precision 490), in every case, ReiserFS was nearly twice as fast completing the install. Didn't matter how the disk was partitioned either. It is a screaming speed machine. Further, launching applications, and playing with KVM, it was also noticeably faster than it's XFS competition.
However, XFS did have much better storage management in the way of sqeezing out every last byte on the drive. In fact, on bare bones installs, XFS gave me 10% more storage space than ReiserFS.
Conclusion? If you're after speed, from what I gathered last night, ReiserFS screams. If you're looking for maximized disk space, XFS is the clear winner there. Was the disk space gain worth the wait of the install? Yeah, probably. But man, post-install, launching applications with ReiserFS was still noticeably faster than XFS.
I'm curious about these, and will be benchmarking some more in the future. Expect follow-up posts on this topic.