We use an x86 router as school hotspot since 1 year.
It authenticates clients by mac address.
No problem until ROS 6.7 upgrade.
Now CPU goes randomly to 100 %.
Randomly means that this could happen after one hour or after five days.
ROS Watchdog is unable to detect this situation.
When this issue happens clients are redirected to login page and an error appear in log. Only way to fix it until the next time is to reboot.
I already sent autosupout file to mikrotik support.
Mikrotik support sent me a v6.8 release candidate.
I will update the forum if the problem persist or not.
write email to support@mikrotik.com to access pre-release page
The candidate release solved the problem. 
The candidate release solved the problem.
the problem it’s again here, currently I’m using 6.32.2
This time the CPU goes to 100% after few minutes after startup.
Profiler reports “management” as the most consuming CPU process (70%)
What does it mean?
I’ve assigned more CPU cores to the VM, how to let routerOS to recognize them?