PF works like a charm. Without doubt.Despite of that, PF don't require the HD and the main bottlenecks are de CPU and memory (and NIC and the driver, of course).
I suspect an error in your PF logging system.PD. 'Urgent' means the same words says: urgent. If you see some message related to PF in your /var/log/messages you should considerate it important (it's urgent!). See at pfctl man pages, -x flag.
-- Thanks, Jordi Espasa Clofent
