• print java heap summary

jmap -heap <PID>

link:heap-summary-demo[Heap Summary Demo]

• generate heap dump(Linux 32)

jmap -dump:format=b,file=heap.hprof JAVA_PID

• generate heap dump(Linux 64)

jmap -J-d64 -dump:format=b,file=heap.hprof JAVA_PID

• generate heap dump(Windows)

jmap -dump:format=b,file=heap.hprof JAVA_PID