Jcmd command uses

  jvm

View java processes (jcmd)

jcmd -l

Or ..

jps

Or ..

jinfo -flags pid

View startup parameters (VM.flags)

jcmd pid VM.flags

Or ..

jps -lvm

View live objects (GC.class_histogram)

jcmd <PID> GC.class_histogram
jcmd <PID> GC.class_stats

Or ..

jmap -histo:live <PID>

Or view the entire heap.

jmap -heap pid

Dump memory (GC.heap_dump)

jcmd pid GC.heap_dump demo.hprof

Or ..

jmap -dump:live,file=demo.hprof

View thread stack (Thread.print)

jcmd <PID> Thread.print

Or ..

jstack <PID>

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