I am not sure of fwlogwatch, but excessive logging will make Astaro drag. Check your logs and see if you have many entries being made. If so, make Drop rules for the packet activity in question...
Sargam, the fwlogwatch handles your kernel logfile every night. If your log is very large, the fwlogwatch process needs very much of your cpu. Define as SecApp said, drop rules in your packet filter. Drop all broadcasts and enquiries to port 135 on your external interface. That should help you. Maybe you can drop all netbios (135-139) enquiries to your external nic.
