I've tested all these filesystems here:
http://rwmj.wordpress.com/2009/11/08/filesystem-metadata-overhead/
--
Richard Jones, Virtualization Group, Red Hat
http://people.redhat.com/~rjones
virt-top is 'top' for virtual machines. Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://et.redhat.com/~rjones/virt-top