'\" t .\" Copyright (c) 2004, 2013, Oracle and/or its affiliates. All rights reserved. .\" Arch: generic .\" Software: JDK 8 .\" Date: 21 November 2013 .\" SectDesc: Troubleshooting Tools .\" Title: jmap.1 .\" .if n .pl 99999 .TH jmap 1 "21 November 2013" "JDK 8" "Troubleshooting Tools" .\" ----------------------------------------------------------------- .\" * Define some portability stuff .\" ----------------------------------------------------------------- .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .\" http://bugs.debian.org/507673 .\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" ----------------------------------------------------------------- .\" * set default formatting .\" ----------------------------------------------------------------- .\" disable hyphenation .nh .\" disable justification (adjust text to left margin only) .ad l .\" ----------------------------------------------------------------- .\" * MAIN CONTENT STARTS HERE * .\" ----------------------------------------------------------------- .SH NAME jmap \- Prints shared object memory maps or heap memory details for a process, core file, or remote debug server\&. This command is experimental and unsupported\&. .SH SYNOPSIS .sp .nf \fBjmap\fR [ \fIoptions\fR ] \fIpid\fR .fi .nf \fBjmap\fR [ \fIoptions\fR ] \fIexecutable\fR \fIcore\fR .fi .nf \fBjmap\fR [ \fIoptions\fR ] [ \fIpid\fR ] \fIserver\-id\fR@ ] \fIremote\-hostname\-or\-IP\fR .fi .sp .TP \fIoptions\fR The command-line options\&. See Options\&. .TP \fIpid\fR The process ID for which the memory map is to be printed\&. The process must be a Java process\&. To get a list of Java processes running on a machine, use the jps(1) command\&. .TP \fIexecutable\fR The Java executable from which the core dump was produced\&. .TP \fIcore\fR The core file for which the memory map is to be printed\&. .TP \fIremote-hostname-or-IP\fR The remote debug server \f3hostname\fR or \f3IP\fR address\&. See jsadebugd(1)\&. .TP \fIserver-id\fR An optional unique ID to use when multiple debug servers are running on the same remote host\&. .SH DESCRIPTION The \f3jmap\fR command prints shared object memory maps or heap memory details of a specified process, core file, or remote debug server\&. If the specified process is running on a 64-bit Java Virtual Machine (JVM), then you might need to specify the \f3-J-d64\fR option, for example: \f3jmap\fR\f3-J-d64 -heap pid\fR\&. .PP \fINote:\fR This utility is unsupported and might not be available in future releases of the JDK\&. On Windows Systems where the \f3dbgeng\&.dll\fR file is not present, Debugging Tools For Windows must be installed to make these tools work\&. The \f3PATH\fR environment variable should contain the location of the \f3jvm\&.dll\fR file that is used by the target process or the location from which the crash dump file was produced, for example: \f3set PATH=%JDK_HOME%\ejre\ebin\eclient;%PATH%\fR\&. .SH OPTIONS .TP When no option is used, the \f3jmap\fR command prints shared object mappings\&. For each shared object loaded in the target JVM, the start address, size of the mapping, and the full path of the shared object file are printed\&. This behavior is similar to the Oracle Solaris \f3pmap\fR utility\&. .TP -dump:[live,] format=b, file=\fIfilename\fR .br Dumps the Java heap in \f3hprof\fR binary format to \f3filename\fR\&. The \f3live\fR suboption is optional, but when specified, only the active objects in the heap are dumped\&. To browse the heap dump, you can use the jhat(1) command to read the generated file\&. .TP -finalizerinfo .br Prints information about objects that are awaiting finalization\&. .TP -heap .br Prints a heap summary of the garbage collection used, the head configuration, and generation-wise heap usage\&. In addition, the number and size of interned Strings are printed\&. .TP -histo[:live] .br Prints a histogram of the heap\&. For each Java class, the number of objects, memory size in bytes, and the fully qualified class names are printed\&. The JVM internal class names are printed with an asterisk (*) prefix\&. If the \f3live\fR suboption is specified, then only active objects are counted\&. .TP -clstats .br Prints class loader wise statistics of Java heap\&. For each class loader, its name, how active it is, address, parent class loader, and the number and size of classes it has loaded are printed\&. .TP -F .br Force\&. Use this option with the \f3jmap -dump\fR or \f3jmap -histo\fR option when the pid does not respond\&. The \f3live\fR suboption is not supported in this mode\&. .TP -h .br Prints a help message\&. .TP -help .br Prints a help message\&. .TP -J\fIflag\fR .br Passes \f3flag\fR to the Java Virtual Machine where the \f3jmap\fR command is running\&. .SH SEE\ ALSO .TP 0.2i \(bu jhat(1) .TP 0.2i \(bu jps(1) .TP 0.2i \(bu jsadebugd(1) .RE .br 'pl 8.5i 'bp