Java process demoted to single CPU
please help on this issue.
I take care of a production enterprise application , it is a java process quite complex that is a middleware application.
The process runs 24 hours a day. Usage cpu is 60% mean value all day.
The process have some burst of cpu usage at 100% usage in the afternoon.
The process runs in a WMWARE virtual Server:
the server is configured 2 CPU, 4GB ram;
the server is installed as a Linux Kernel 2.6.18-274.12.1.el5.
Java version installed is 1.6.0_16;
In a unpredictable moment, mean 2 times a week, the processes is misteriously demoted to Single CPU,
it takes maximum 50% CPU and application becomes is unavailable because not capable to serve all requests.
Does anybody knows if there is an "auto demoting to single cpu" mechanism in Java ?
Or in Linux?
Or in Wmware?
thanks in advance
Re: Java process demoted to single CPU
I'd guess (and only a guess) its VMWare problem. I say this based upon experience running the JVM in VMWare in which unexpected issues arise with memory management and garbage collection, which in turn relates to CPU usage. For instance if your code hits the memory ceiling and must garbage collect before it can allocate anything else (you might wish to modify the GC configuration to see if this alleviates anything).