Plesk 12.x / Linux :: MySQL Process Running Unlimited With High CPU?

I have a single mysql process that never stops and running with 10-200% CPU load: URL....

I restart mysql => process coming back
I restart server => process coming back
I kill process => process coming back

I have run:
# mysqladmin -uadmin -p`cat /etc/psa/.psa.shadow` -i 1 processlist
but there was noting that runs >10min.

Code:
> SHOW FULL PROCESSLIST;
+------+-------+-----------+------+---------+------+-------+-----------------------+
| Id | User | Host | db | Command | Time | State | Info |
+------+-------+-----------+------+---------+------+-------+-----------------------+
| 328 | admin | localhost | psa | Sleep | 56 | | NULL |
| 8110 | admin | localhost | NULL | Query | 0 | init | SHOW FULL PROCESSLIST |
+------+-------+-----------+------+---------+------+-------+-----------------------+
2 rows in set (0.00 sec)
I have strace the PID

Code:
# timeout 1m strace -f -c -p 5873
Process 5873 attached with 30 threads - interrupt to quit
Process 10499 attached (waiting for parent)
Process 10499 resumed (parent 5873 ready)
Process 10502 attached (waiting for parent)
Process 10502 resumed (parent 5873 ready)
Process 10503 attached (waiting for parent)

[code]....

I found with google a hint for high cpu URL....I have deinstalled "health monitor" module, but that was not the reason.I use plesk 12.0.18 Update #38 with CentOS 6.6 (Final).