oracle Qmnc uses high cpu

hello, I have an old Oracle production server 10.1, on HPUX ,     Model:      9000/800, HP Container, No RAC,  64GB memory, 8 processor cores, at the time of problem 12GB free. 4 of the 8 cores running over 90%. other 4 cores are ok so average is 30%. We have 4 databases running on this HP container, two are live, two are test, at the time of problem, the test database were not being used, and no entry connected in listener log in past 3 days. only connections were the 2 live databases.

The problem is that since the qmnc is busy on something (high cpu), the child process it spawned are left as defunct zombie processes not being cleaned, it had 3782 zombie processes left by the 4 databases's qmnc processes. brought the oracle processes to 4096 limit according to our current setting. all new connections to oracle databases were failed, even to switch to oracle as su - oracle.