Hi
I also had this problem several times and was able to solve it as follows. As soon as I deleted the “ip dhcp snooping vlan xxx” from the configuration, the CPU went from >75-80% “high SISF main thread” back to approx. 2-5%.
Since it was not a solution for the customer and me to switch off the feature, I solved it with the following global switch configuration:
device-tracking policy DT-PROGRAMMATIC
no protocol ndp
no protocol dhcp6
First the “ip dhcp snooping vlan xxx” configuration has to be removed and then the device tracing parameters can be added on global level, after that the “ip dhcp snooping vlan xxx” configuration can be added again.
I hope it helps you too!
Regards, Alex