CPU utilization

[Stefano PASCALI]

Hi FR folks,

I got a strange cpu load on my FR installation. Sometimes CPU utilization rises to 100% and FR service doesn't respond anymore to the clients. I got two virtual servers enabled: default and inner-tunnel and their configurations are the provided ones by the FR installation.
Configuration details in the following:

OS: Ubuntu server 14.04
Deamon: freeradius 2.1.12+dfsg-1.2ubuntu8 amd64
2 vcpu
RAM 4GB

Users on freeradius MySQL (5.x) DB installed on a different virtual host on the same hosting server.

Hosting server (Ubuntu server 14.04 + Xen 4.3) HP PL G5
CPU: 2 x Intel(R) Xeon(R) CPU E7330 @ 2.40GHz - cpu cores 4; [total cores 2x4 = 8]
RAM 16GiB

Do you have any ideas to solve my issue?
Hope someone help me.

Regards
Stefano