o Enable noatime on the counter db files.
o Tune the cache-size configuration directive to match your needs.
The cache size should be set to 2-3 * number of available nas ports.
+o Keep the database in a memory mapped file if you can help. Backup the
+ file every 10 mins to the disk and copy it to the memory mapped one
+ on server startup.
------------ RADUTMP MODULE ----------
o Enable noatime on the radutmp file