[CentOS] Poor rsync performance after upgrade from 5.8 x86 to 6.3 x64

Greetings-

The subject sums it up...

I have a Dell 2950 acting as a general purpose 'storage' machine, handling some NFS work for some local servers, and also pulling in rsync backups of some largish filesystems over SSH. These backups, prior to the upgrade were taking about 6 hours to complete (MANY small files). Now, after the upgrade, the same backups are taking about 16 hours to complete. The actual storage array in question (PERC 5i running RAID5) has not changed in any way, nor the filesystem (ext3). The only hardware change was an upgrade from 2GB to 16GB of RAM.

Are there any issues with the filesystem being created by a 32bit OS, now used on a 64bit OS? I find it hard to believe rsync has gotten 'slower' in later versions.. :)

All tips, pointers, suggestions, etc welcome.

--Tim