OS Manuals

/usr/lib/jvm/java-13-openjdk/bin/jmap

From openjdk-13 13.0.14.5-r8 (os), captured 2026-11-05 by running jmap --help (exit 0). permalink

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.