We are busy evaluating an ASA5520 + AIP-SSM-20, and are noticing that if we push 30mbit through the firewall, the CPU goes up to about 70%. I'm talking about a single FTP transfer. The inspection load, however, stays below 10%.
We are not using any custom signatures at this stage, and have a reasonably standard configuration. Cisco quote 375MBps for the device, but at this rate, I cannot see it pushing 50 - what can we possibly look for that could be causing the high CPU?