CCR 1016-12G CPU maxed out

Hello forum members,
I am using CCR1016-12G as a PPPoE server with around 450 customers. There is ~350 mbps throughput having 500 simple queues, 12 queue tree, 2 filter rules, 13 NAT rules and 13 mangle rules. But when the traffic is ~200 mbps the CPU usage is CPU load is ~20-25% having same queues and filter rules.

On that nat rules,

Are you using src-nat or masquerade on the public interface.

If you use masquerade and a few of the tunnels starts disconnecting then you will see that high CPU usage.

Check out this video a very good presentation that describes your problem

https://www.youtube.com/watch?v=D80_a_O86jc