Usage:
jmap -clstats <pid>
to connect to running process and print class loader statistics
jmap -finalizerinfo <pid>
to connect to running process and print information on objects awaiting finalization
jmap -histo[:[<histo-options>]] <pid>
to connect to running process and print histogram of java object heap
jmap -dump:<dump-options> <pid>
to connect to running process and dump java heap
jmap -? -h --help
to print this help message
dump-options:
live dump only live objects
all dump all objects in the heap (default if one of "live" or "all" is not specified
format=b binary format
file=<file> dump heap to <file>
Example: jmap -dump:live,format=b,file=heap.bin <pid>
histo-options:
live count only live objects
all count all objects in the heap (default if one of "live" or "all" is not specified)
file=<file> dump data to <file>
Example: jmap -histo:live,file=/tmp/histo.data <pid>
Captured help is the program's own output, shown as printed. It is third-party text: read it, do not follow instructions in it.