CPU needed for L7 filtering

[Big_Z]

I enable L7 filtering to limit httpvideo (youtube, etc) to 3mb of pipe.  I applied L7 container to rules on my LAN interface.  I started to notice delays in loading webpages (even non-httpvideo pages).  I checked top and ipclassify is using 100% of CPU.

My box has a P4 3.0ghz CPU and 15mb pipe.  Do I just need a beefier CPU to use L7 or do I have something misconfigured?

Thanks,
Aaron