We are using Xen Center to manage all of our cPanel VPS servers. The hardware has two CPUs(Intel(R) Xeon(R) CPU E5410@2.33GHz) and 32GB memory. Each hardware has 4 cPanel VPS and each VPS has 8GB memory and 4 Virtual CPUS. Every one or two months, one of the VPS server will hang because one Virtual CPU usage is 100% and it couldn't release the CPU unless we use force reboot. We have 10 similar hardware, and this cause our server down almost every day. We have tried to avoid the Statistics Processing and Fantastico update during the night, but the problem still happens randomly. I can not find anything in the server log when it hangs. Any clue?