1JMAP(1)                          JDK Commands                          JMAP(1)
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NAME

6       jmap - print details of a specified process
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SYNOPSIS

9       Note: This command is experimental and unsupported.
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11       jmap [options] pid
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13       options
14              This  represents the jmap command-line options.  See Options for
15              the jmap Command.
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17       pid    The process ID for which the information specified  by  the  op‐
18              tions is to be printed.  The process must be a Java process.  To
19              get a list of Java processes running on a  machine,  use  either
20              the  ps  command  or,  if the JVM processes are not running in a
21              separate docker instance, the jps command.
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23              Note: JDK 10 has added support for using the Attach API when at‐
24              taching  to Java processes running in a separate docker process.
25              However, the jps command will not list the  JVM  processes  that
26              are running in a separate docker instance.  If you are trying to
27              connect a Linux host with a Virtual Machine that is in a  docker
28              container,  you  must use tools such as ps to look up the PID of
29              the JVM.
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DESCRIPTION

32       The jmap command prints details of a specified running process.
33
34       Note:
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36       This command is unsupported and might not be available  in  future  re‐
37       leases  of the JDK.  On Windows Systems where the dbgeng.dll file isn't
38       present, the Debugging Tools for Windows  must  be  installed  to  make
39       these tools work.  The PATH environment variable should contain the lo‐
40       cation of the jvm.dll file that's used by the target process or the lo‐
41       cation from which the core dump file was produced.
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OPTIONS FOR THE JMAP COMMAND

44       -clstats pid
45              Connects to a running process and prints class loader statistics
46              of Java heap.
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48       -finalizerinfo pid
49              Connects to a running process and prints information on  objects
50              awaiting finalization.
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52       -histo[:live] pid
53              Connects to a running process and prints a histogram of the Java
54              object heap.  If the live suboption is specified, it then counts
55              only live objects.
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57       -dump:dump_options pid
58              Connects  to  a  running  process  and dumps the Java heap.  The
59              dump_options include:
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61              · live --- When specified, dumps only the live objects;  if  not
62                specified, then dumps all objects in the heap.
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64              · format=b --- Dumps the Java heap in hprof binary format
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66              · file=filename --- Dumps the heap to filename
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68              Example: jmap -dump:live,format=b,file=heap.bin pid
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72JDK 14                               2020                              JMAP(1)