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8227602: Update nroff version of man pages
Reviewed-by: mchung
This commit is contained in:
Jonathan Gibbons
parent
cd18508b2f
commit
27c77d3d29
8 changed files with 1337 additions and 727 deletions
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@ -109,7 +109,7 @@ the main class.
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.SH DESCRIPTION
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.PP
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The \f[CB]java\f[R] command starts a Java application.
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It does this by starting the Java Runtime Environment (JRE), loading the
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It does this by starting the Java Virtual Machine (JVM), loading the
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specified class, and calling that class\[aq]s \f[CB]main()\f[R] method.
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The method must be declared \f[CB]public\f[R] and \f[CB]static\f[R], it must
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not return any value, and it must accept a \f[CB]String\f[R] array as a
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@ -566,7 +566,7 @@ marks (for example \f[CB]\-Dfoo="foo\ bar"\f[R]).
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.RS
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.RE
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.TP
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.B \f[CB]\-disableassertions\f[R][\f[CB]:\f[R][\f[I]packagename\f[R]]...|\f[CB]:\f[R]\f[I]classname\f[R]] or \f[CB]\-da\\[\f[R]:\f[CB]\\[*packagename*\\]...|\f[R]:`\f[I]classname\f[R]]
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.B \f[CB]\-disableassertions\f[R][\f[CB]:\f[R][\f[I]packagename\f[R]]...|\f[CB]:\f[R]\f[I]classname\f[R]] or \f[CB]\-da\f[R][\f[CB]:\f[R][\f[I]packagename\f[R]]...|\f[CB]:\f[R]\f[I]classname\f[R]]
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Disables assertions.
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By default, assertions are disabled in all packages and classes.
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With no arguments, \f[CB]\-disableassertions\f[R] (\f[CB]\-da\f[R]) disables
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@ -606,7 +606,7 @@ Disables assertions in all system classes.
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.RS
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.RE
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.TP
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.B \f[CB]\-enableassertions\f[R][\f[CB]:\f[R][\f[I]packagename\f[R]]...|\f[CB]:\f[R]\f[I]classname\f[R]] or \f[CB]\-ea\\[\f[R]:\f[CB]\\[*packagename*\\]...|\f[R]:`\f[I]classname\f[R]]
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.B \f[CB]\-enableassertions\f[R][\f[CB]:\f[R][\f[I]packagename\f[R]]...|\f[CB]:\f[R]\f[I]classname\f[R]] or \f[CB]\-ea\f[R][\f[CB]:\f[R][\f[I]packagename\f[R]]...|\f[CB]:\f[R]\f[I]classname\f[R]]
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Enables assertions.
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By default, assertions are disabled in all packages and classes.
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With no arguments, \f[CB]\-enableassertions\f[R] (\f[CB]\-ea\f[R]) enables
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@ -659,6 +659,7 @@ Prints the help message to the output stream.
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.TP
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.B \f[CB]\-javaagent:\f[R]\f[I]jarpath\f[R][\f[CB]=\f[R]\f[I]options\f[R]]
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Loads the specified Java programming language agent.
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See \f[CB]java.lang.instrument\f[R].
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.RS
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.RE
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.TP
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|
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@ -718,12 +719,12 @@ Displays information about the modules in use.
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.RE
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.TP
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.B \f[CB]\-\-version\f[R]
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Prints product version to the error stream and exits.
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Prints product version to the output stream and exits.
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.RS
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.RE
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.TP
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.B \f[CB]\-version\f[R]
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Prints product version to the output stream and exits.
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Prints product version to the error stream and exits.
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.RS
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.RE
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.TP
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|
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@ -747,7 +748,7 @@ limitations by enabling the launcher to expand the contents of argument
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files after shell expansion, but before argument processing.
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Contents in the argument files are expanded because otherwise, they
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would be specified on the command line until the
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\f[CB]\-Xdisable\-\@files\f[R] option was encountered.
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\f[CB]\-\-disable\-\@files\f[R] option was encountered.
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.RS
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.PP
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The argument files can also contain the main class name and all options.
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@ -856,7 +857,7 @@ are compiled to native code.
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.TP
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.B \f[CB]\-Xmn\f[R] \f[I]size\f[R]
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Sets the initial and maximum size (in bytes) of the heap for the young
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generation (nursery).
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generation (nursery) in the generational collectors.
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Append the letter \f[CB]k\f[R] or \f[CB]K\f[R] to indicate kilobytes,
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\f[CB]m\f[R] or \f[CB]M\f[R] to indicate megabytes, or \f[CB]g\f[R] or
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\f[CB]G\f[R] to indicate gigabytes.
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@ -866,8 +867,10 @@ If the size for the young generation is too small, then a lot of minor
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garbage collections are performed.
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If the size is too large, then only full garbage collections are
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performed, which can take a long time to complete.
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It is recommended that you keep the size for the young generation
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greater than 25% and less than 50% of the overall heap size.
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It is recommended that you do not set the size for the young generation
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for the G1 collector, and keep the size for the young generation greater
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than 25% and less than 50% of the overall heap size for other
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collectors.
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The following examples show how to set the initial and maximum size of
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young generation to 256 MB using various units:
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.RS
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@ -887,7 +890,7 @@ size of the heap for the young generation, you can use
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.RE
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.TP
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.B \f[CB]\-Xms\f[R] \f[I]size\f[R]
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Sets the initial size (in bytes) of the heap.
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Sets the minimum and initial size (in bytes) of the heap.
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This value must be a multiple of 1024 and greater than 1 MB.
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Append the letter \f[CB]k\f[R] or \f[CB]K\f[R] to indicate kilobytes,
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\f[CB]m\f[R] or \f[CB]M\f[R] to indicate megabytes, \f[CB]g\f[R] or \f[CB]G\f[R]
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@ -904,16 +907,18 @@ MB using various units:
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\f[R]
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.fi
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.PP
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If you don\[aq]t set this option, then the initial size is set as the
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sum of the sizes allocated for the old generation and the young
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generation.
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Instead of the \f[CB]\-Xms\f[R] option to set both the minimum and initial
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size of the heap, you can use \f[CB]\-XX:MinHeapSize\f[R] to set the
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minimum size and \f[CB]\-XX:InitialHeapSize\f[R] to set the initial size.
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.PP
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If you don\[aq]t set this option, the initial size is set as the sum of
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the sizes allocated for the old generation and the young generation.
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The initial size of the heap for the young generation can be set using
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the \f[CB]\-Xmn\f[R] option or the \f[CB]\-XX:NewSize\f[R] option.
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.RE
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.TP
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.B \f[CB]\-Xmx\f[R] \f[I]size\f[R]
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Specifies the maximum size (in bytes) of the memory allocation pool in
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bytes.
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Specifies the maximum size (in bytes) of the heap.
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This value must be a multiple of 1024 and greater than 2 MB.
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Append the letter \f[CB]k\f[R] or \f[CB]K\f[R] to indicate kilobytes,
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\f[CB]m\f[R] or \f[CB]M\f[R] to indicate megabytes, or \f[CB]g\f[R] or
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@ -1205,13 +1210,6 @@ or directories.
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.RS
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.RE
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.TP
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.B \f[CB]\-\-disable\-\@files\f[R]
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Can be used anywhere on the command line, including in an argument file,
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to prevent further \f[CB]\@\f[R]\f[I]filename\f[R] expansion.
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This option stops expanding \f[CB]\@\f[R]\-argfiles after the option.
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.RS
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.RE
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.TP
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.B \f[CB]\-\-source\f[R] \f[I]version\f[R]
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Sets the version of the source in source\-file mode.
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.RS
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@ -1392,32 +1390,13 @@ By default this option is disabled.
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.RS
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.RE
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.TP
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.B \f[CB]\-XX:+FlightRecorder\f[R]
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Enables the use of Java Flight Recorder (JFR) during the runtime of the
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application.
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.RS
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.RS
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.PP
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\f[B]Note:\f[R] The \f[CB]\-XX:+FlightRecorder\f[R] option is no longer
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required to use JFR.
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This was a change made in JDK 8u40.
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.RE
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.RE
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.TP
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.B \f[CB]\-XX:FlightRecorderOptions=\f[R]\f[I]parameter\f[R]\f[CB]=\f[R]\f[I]value\f[R]
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.B \f[CB]\-XX:FlightRecorderOptions=\f[R]\f[I]parameter\f[R]\f[CB]=\f[R]\f[I]value\f[R] (or)\f[CB]\-XX:FlightRecorderOptions:\f[R]\f[I]parameter\f[R]\f[CB]=\f[R]\f[I]value\f[R]
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Sets the parameters that control the behavior of JFR.
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.RS
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.PP
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The following list contains the available JFR
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\f[I]parameter\f[R]\f[CB]=\f[R]\f[I]value\f[R] entries:
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.TP
|
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.B \f[CB]allow_threadbuffers_to_disk=\f[R]{\f[CB]true\f[R]|\f[CB]false\f[R]}
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Specifies whether thread buffers are written directly to disk if the
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buffer thread is blocked.
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By default, this parameter is disabled.
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.RS
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.RE
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.TP
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.B \f[CB]globalbuffersize=\f[R]\f[I]size\f[R]
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Specifies the total amount of primary memory used for data retention.
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The default value is based on the value specified for
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@ -1492,7 +1471,8 @@ performance.
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.TP
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.B \f[CB]threadbuffersize=\f[R]\f[I]size\f[R]
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Specifies the per\-thread local buffer size (in bytes).
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By default, the local buffer size is set to 8 kilobytes.
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By default, the local buffer size is set to 8 kilobytes, with a minimum
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value of 4 kilobytes.
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Overriding this parameter could reduce performance and is not
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recommended.
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.RS
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@ -2978,19 +2958,17 @@ Enables Java heap optimization.
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This sets various parameters to be optimal for long\-running jobs with
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intensive memory allocation, based on the configuration of the computer
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(RAM and CPU).
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By default, the option is disabled and the heap isn't optimized.
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By default, the option is disabled and the heap sizes are configured
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less aggressively.
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.RS
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.RE
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.TP
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.B \f[CB]\-XX:+AlwaysPreTouch\f[R]
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Enables touching of every page on the Java heap during JVM
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initialization.
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This gets all pages into memory before entering the \f[CB]main()\f[R]
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method.
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The option can be used in testing to simulate a long\-running system
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with all virtual memory mapped to physical memory.
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By default, this option is disabled and all pages are committed as JVM
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heap space fills.
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Requests the VM to touch every page on the Java heap after requesting it
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from the operating system and before handing memory out to the
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application.
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By default, this option is disabled and all pages are committed as the
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application uses the heap space.
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.RS
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.RE
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.TP
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@ -3026,12 +3004,10 @@ initiating occupancy fraction.
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.RS
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.PP
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The following example shows how to set the factor to 20%:
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.IP
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.nf
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\f[CB]
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>\ \ \ `\-XX:CMSInitiatingOccupancyFraction=20`
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\f[R]
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.fi
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.RS
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.PP
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\f[CB]\-XX:CMSInitiatingOccupancyFraction=20\f[R]
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.RE
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.RE
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.TP
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.B \f[CB]\-XX:CMSIncrementalDutySafetyFactor=\f[R]\f[I]percent\f[R]
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|
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@ -3095,11 +3071,14 @@ deprecated \f[CB]\-XX:+UseConcMarkSweepGC\f[R] option and the
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.RS
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.RE
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.TP
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.B \f[CB]\-XX:+ExplicitGCInvokesConcurrentAndUnloadsClasses\f[R]
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Enables invoking of concurrent GC by using the \f[CB]System.gc()\f[R]
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request and unloading of classes during the concurrent GC cycle.
|
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This option is disabled by default and can be enabled only with the
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deprecated \f[CB]\-XX:+UseConcMarkSweepGC\f[R] option.
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.B \f[CB]\-XX:G1AdaptiveIHOPNumInitialSamples=\f[R]\f[I]number\f[R]
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When \f[CB]\-XX:UseAdaptiveIHOP\f[R] is enabled, this option sets the
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number of completed marking cycles used to gather samples until G1
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adaptively determines the optimum value of
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\f[CB]\-XX:InitiatingHeapOccupancyPercent\f[R].
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Before, G1 uses the value of
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\f[CB]\-XX:InitiatingHeapOccupancyPercent\f[R] directly for this purpose.
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The default value is 3.
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.RS
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.RE
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.TP
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|
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@ -3107,10 +3086,8 @@ deprecated \f[CB]\-XX:+UseConcMarkSweepGC\f[R] option.
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Sets the size of the regions into which the Java heap is subdivided when
|
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using the garbage\-first (G1) collector.
|
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The value is a power of 2 and can range from 1 MB to 32 MB.
|
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The goal is to have around 2048 regions based on the minimum Java heap
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size.
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The default region size is determined ergonomically based on the heap
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size.
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size with a goal of approximately 2048 regions.
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.RS
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.PP
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The following example sets the size of the subdivisions to 16 MB:
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|
@ -3137,8 +3114,6 @@ The default value is 60 percent of your Java heap.
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.PP
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This is an experimental flag.
|
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This setting replaces the \f[CB]\-XX:DefaultMaxNewGenPercent\f[R] setting.
|
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.PP
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This setting isn\[aq]t available in Java HotSpot VM build 23 or earlier.
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.RE
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.TP
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.B \f[CB]\-XX:G1MixedGCCountTarget=\f[R]\f[I]number\f[R]
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@ -3148,8 +3123,6 @@ cycle to collect old regions with at most
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The default is 8 mixed garbage collections.
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The goal for mixed collections is to be within this target number.
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.RS
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.PP
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This setting isn\[aq]t available in Java HotSpot VM build 23 or earlier.
|
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.RE
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.TP
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.B \f[CB]\-XX:G1MixedGCLiveThresholdPercent=\f[R]\f[I]percent\f[R]
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@ -3161,8 +3134,6 @@ The default occupancy is 85 percent.
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This is an experimental flag.
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This setting replaces the
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\f[CB]\-XX:G1OldCSetRegionLiveThresholdPercent\f[R] setting.
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.PP
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This setting isn\[aq]t available in Java HotSpot VM build 23 or earlier.
|
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.RE
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.TP
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.B \f[CB]\-XX:G1NewSizePercent=\f[R]\f[I]percent\f[R]
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@ -3173,8 +3144,6 @@ The default value is 5 percent of your Java heap.
|
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.PP
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This is an experimental flag.
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This setting replaces the \f[CB]\-XX:DefaultMinNewGenPercent\f[R] setting.
|
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.PP
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This setting isn\[aq]t available in Java HotSpot VM build 23 or earlier.
|
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.RE
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.TP
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.B \f[CB]\-XX:G1OldCSetRegionThresholdPercent=\f[R]\f[I]percent\f[R]
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@ -3182,8 +3151,6 @@ Sets an upper limit on the number of old regions to be collected during
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a mixed garbage collection cycle.
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The default is 10 percent of the Java heap.
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.RS
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.PP
|
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This setting isn\[aq]t available in Java HotSpot VM build 23 or earlier.
|
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.RE
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.TP
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.B \f[CB]\-XX:G1ReservePercent=\f[R]\f[I]percent\f[R]
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|
@ -3202,10 +3169,20 @@ The following example sets the reserved heap to 20%:
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.RE
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.RE
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.TP
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.B \f[CB]\-XX:InitialHeapOccupancyPercent=\f[R]\f[I]percent\f[R]
|
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Sets the Java heap occupancy threshold that triggers a marking cycle.
|
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The default occupancy is 45 percent of the entire Java heap.
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.B \f[CB]\-XX:+G1UseAdaptiveIHOP\f[R]
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Controls adaptive calculation of the old generation occupancy to start
|
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background work preparing for an old generation collection.
|
||||
If enabled, G1 uses \f[CB]\-XX:InitiatingHeapOccupancyPercent\f[R] for the
|
||||
first few times as specified by the value of
|
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\f[CB]\-XX:G1AdaptiveIHOPNumInitialSamples\f[R], and after that adaptively
|
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calculates a new optimum value for the initiating occupancy
|
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automatically.
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Otherwise, the old generation collection process always starts at the
|
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old generation occupancy determined by
|
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\f[CB]\-XX:InitiatingHeapOccupancyPercent\f[R].
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.RS
|
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.PP
|
||||
The default is enabled.
|
||||
.RE
|
||||
.TP
|
||||
.B \f[CB]\-XX:InitialHeapSize=\f[R]\f[I]size\f[R]
|
||||
|
|
@ -3276,15 +3253,18 @@ to 4:
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.RE
|
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.TP
|
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.B \f[CB]\-XX:InitiatingHeapOccupancyPercent=\f[R]\f[I]percent\f[R]
|
||||
Sets the percentage of the heap occupancy (0 to 100) at which to start a
|
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concurrent GC cycle.
|
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It\[aq]s used by garbage collectors that trigger a concurrent GC cycle
|
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based on the occupancy of the entire heap, not just one of the
|
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generations (for example, the G1 garbage collector).
|
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Sets the percentage of the old generation occupancy (0 to 100) at which
|
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to start the first few concurrent marking cycles for the G1 garbage
|
||||
collector.
|
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.RS
|
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.PP
|
||||
By default, the initiating value is set to 45%.
|
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A value of 0 implies nonstop GC cycles.
|
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A value of 0 implies nonstop concurrent GC cycles from the beginning
|
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until G1 adaptively sets this value.
|
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.PP
|
||||
See also the \f[CB]\-XX:G1UseAdaptiveIHOP\f[R] and
|
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\f[CB]\-XX:G1AdaptiveIHOPNumInitialSamples\f[R] options.
|
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.PP
|
||||
The following example shows how to set the initiating heap occupancy to
|
||||
75%:
|
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.RS
|
||||
|
|
@ -3298,7 +3278,9 @@ Sets a target for the maximum GC pause time (in milliseconds).
|
|||
This is a soft goal, and the JVM will make its best effort to achieve
|
||||
it.
|
||||
The specified value doesn\[aq]t adapt to your heap size.
|
||||
By default, there\[aq]s no maximum pause time value.
|
||||
By default, for G1 the maximum pause time target is 200 milliseconds.
|
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The other generational collectors do not use a pause time goal by
|
||||
default.
|
||||
.RS
|
||||
.PP
|
||||
The following example shows how to set the maximum target pause time to
|
||||
|
|
@ -3332,13 +3314,6 @@ allocated memory to 80 MB using various units:
|
|||
\f[R]
|
||||
.fi
|
||||
.PP
|
||||
On Oracle Solaris 7 and Oracle Solaris 8 SPARC platforms, the upper
|
||||
limit for this value is approximately 4,000 MB minus overhead amounts.
|
||||
On Oracle Solaris 2.6 and x86 platforms, the upper limit is
|
||||
approximately 2,000 MB minus overhead amounts.
|
||||
On Linux platforms, the upper limit is approximately 2,000 MB minus
|
||||
overhead amounts.
|
||||
.PP
|
||||
The \f[CB]\-XX:MaxHeapSize\f[R] option is equivalent to \f[CB]\-Xmx\f[R].
|
||||
.RE
|
||||
.TP
|
||||
|
|
@ -3450,6 +3425,32 @@ option to keep the Java heap small by reducing the dynamic footprint for
|
|||
embedded applications.
|
||||
.RE
|
||||
.TP
|
||||
.B \f[CB]\-XX:MinHeapSize=\f[R]\f[I]size\f[R]
|
||||
Sets the minimum size (in bytes) of the memory allocation pool.
|
||||
This value must be either 0, or a multiple of 1024 and greater than 1
|
||||
MB.
|
||||
Append the letter \f[CB]k\f[R] or \f[CB]K\f[R] to indicate kilobytes,
|
||||
\f[CB]m\f[R] or \f[CB]M\f[R] to indicate megabytes, or \f[CB]g\f[R] or
|
||||
\f[CB]G\f[R] to indicate gigabytes.
|
||||
The default value is selected at run time based on the system
|
||||
configuration.
|
||||
.RS
|
||||
.PP
|
||||
The following examples show how to set the mimimum size of allocated
|
||||
memory to 6 MB using various units:
|
||||
.IP
|
||||
.nf
|
||||
\f[CB]
|
||||
\-XX:MinHeapSize=6291456
|
||||
\-XX:MinHeapSize=6144k
|
||||
\-XX:MinHeapSize=6m
|
||||
\f[R]
|
||||
.fi
|
||||
.PP
|
||||
If you set this option to 0, then the minimum size is set to the same
|
||||
value as the initial size.
|
||||
.RE
|
||||
.TP
|
||||
.B \f[CB]\-XX:NewRatio=\f[R]\f[I]ratio\f[R]
|
||||
Sets the ratio between young and old generation sizes.
|
||||
By default, this option is set to 2.
|
||||
|
|
@ -3493,23 +3494,13 @@ The \f[CB]\-XX:NewSize\f[R] option is equivalent to \f[CB]\-Xmn\f[R].
|
|||
.RE
|
||||
.TP
|
||||
.B \f[CB]\-XX:ParallelGCThreads=\f[R]\f[I]threads\f[R]
|
||||
Sets the value of the stop\-the\-world (STW) worker threads.
|
||||
This option sets the value of \f[I]threads\f[R] to the number of logical
|
||||
processors.
|
||||
The value of \f[I]threads\f[R] is the same as the number of logical
|
||||
processors up to a value of 8.
|
||||
Sets the number of the stop\-the\-world (STW) worker threads.
|
||||
The default value depends on the number of CPUs available to the JVM and
|
||||
the garbage collector selected.
|
||||
.RS
|
||||
.PP
|
||||
If there are more than 8 logical processors, then this option sets the
|
||||
value of \f[I]threads\f[R] to approximately 5/8 of the logical
|
||||
processors.
|
||||
This works in most cases except for larger SPARC systems where the value
|
||||
of \f[I]threads\f[R] can be approximately 5/16 of the logical processors.
|
||||
.PP
|
||||
The default value depends on the number of CPUs available to the JVM.
|
||||
.PP
|
||||
For example, to set the number of threads for parallel GC to 2, specify
|
||||
the following option:
|
||||
For example, to set the number of threads for G1 GC to 2, specify the
|
||||
following option:
|
||||
.RS
|
||||
.PP
|
||||
\f[CB]\-XX:ParallelGCThreads=2\f[R]
|
||||
|
|
@ -3749,6 +3740,22 @@ This option is enabled by default.
|
|||
To disable the use of TLABs, specify the option \f[CB]\-XX:\-UseTLAB\f[R].
|
||||
.RS
|
||||
.RE
|
||||
.TP
|
||||
.B \f[CB]\-XX:+UseZGC\f[R]
|
||||
Enables the use of the Z garbage collector.
|
||||
This garbage collector is best for providing lowest latency with large
|
||||
Java heaps at some throughput cost.
|
||||
This is an experimental garbage collector, you need to specify
|
||||
\f[CB]\-XX:+UnlockExperimentalVMOptions\f[R] before \f[CB]\-XX:+UseZGC\f[R]
|
||||
on the command line.
|
||||
.RS
|
||||
.PP
|
||||
Example:
|
||||
.RS
|
||||
.PP
|
||||
\f[CB]\-XX:+UnlockExperimentalVMOptions\ \-XX:+UseZGC\f[R]
|
||||
.RE
|
||||
.RE
|
||||
.SH DEPRECATED JAVA OPTIONS
|
||||
.PP
|
||||
These \f[CB]java\f[R] options are deprecated and might be removed in a
|
||||
|
|
@ -3788,6 +3795,13 @@ You can enable it only for classes with older versions of the bytecode.
|
|||
.RS
|
||||
.RE
|
||||
.TP
|
||||
.B \f[CB]\-XX:+FlightRecorder\f[R]
|
||||
Enables the use of Java Flight Recorder (JFR) during the runtime of the
|
||||
application.
|
||||
Since JDK 8u40 this option has not been required to use JFR.
|
||||
.RS
|
||||
.RE
|
||||
.TP
|
||||
.B \f[CB]\-XX:+TraceClassLoading\f[R]
|
||||
Enables tracing of classes as they are loaded.
|
||||
By default, this option is disabled and classes aren\[aq]t traced.
|
||||
|
|
@ -3926,8 +3940,8 @@ sign (\f[CB]\@\f[R]), it expands the contents of that file into an
|
|||
argument list just as they would be specified on the command line.
|
||||
.PP
|
||||
The \f[CB]java\f[R] launcher expands the argument file contents until it
|
||||
encounters the \f[CB]\-Xdisable\-\@files\f[R] option.
|
||||
You can use the \f[CB]\-Xdisable\-\@files\f[R] option anywhere on the
|
||||
encounters the \f[CB]\-\-disable\-\@files\f[R] option.
|
||||
You can use the \f[CB]\-\-disable\-\@files\f[R] option anywhere on the
|
||||
command line, including in an argument file, to stop \f[CB]\@\f[R]
|
||||
argument files expansion.
|
||||
.PP
|
||||
|
|
@ -5603,7 +5617,7 @@ Use the following commands and advanced options to achieve lower
|
|||
response times for your application:
|
||||
.RS
|
||||
.PP
|
||||
\f[CB]java\ \-XX:+UseG1GC\ \-Xms26g\ Xmx26g\ \-XX:MaxGCPauseMillis=500\f[R]
|
||||
\f[CB]java\ \-XX:+UseG1GC\ \-XX:MaxGCPauseMillis=100\f[R]
|
||||
.RE
|
||||
.SS Keeping the Java Heap Small and Reducing the Dynamic Footprint of
|
||||
Embedded Applications
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue