How can I know, how many JVM is running?

Well, just to through in my two cents, on most unix/linux variants you can identify processes that have a handle to a specific file, so the count of processes that currently have a file handle to rt.jar (in all of its various versions installed on the machine) should give you a somewhat accurate count of the running JVMs (unless someone is manually looking at one of the rt.jars with an editor or something).

;-)

But, I don't suggest this as the overhead in finding this out is not insignificant, and once again, why do you need the info.

masijade.a at 2007-7-8 22:06:57 >

> Well, just to through in my two cents, on most

> unix/linux variants you can identify processes that

> have a handle to a specific file, so the count of

> processes that currently have a file handle to rt.jar

> (in all of its various versions installed on the

> machine) should give you a somewhat accurate count of

> the running JVMs (unless someone is manually looking

> at one of the rt.jars with an editor or something).

A good idea, but my app-server process does not appear to have *any* jar open.

[ebank2@giskard oc4j]$ ls -l /proc/10038/fd|grep jar

[ebank2@giskard oc4j]$ ps -p 10038

PID TTY TIME CMD

10038 ?00:00:01 java

[ebank2@giskard oc4j]$ ps -p 10038 -f

UIDPID PPID C STIME TTY TIME CMD

ebank210038 10034 0 Jan08 ?00:00:01 java -DUSR=ivan -classpath .:/opt/mqm/java/lib/com.ibm.mq.jar:/opt/mqm/j

BIJ001a at 2007-7-8 22:06:57 >