Looks like something in SNMP service was making it crash, this is for monitoring the cpu/memory usage remotely for those that don’t know.
It seems it may have been making the sudden rush of slowness after otherwise running very well.
since I stopped it we’ve been good, hoping for more. I posted it here as it is not 100% firm this is the core problem yet, but it seems it was, there were a couple log entries about an exception caused by it but not exactly the times it went slow, but near enough that I think the service manager trying to auto restart it may be the cause.