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*** 20,30 ****
.\" or visit www.oracle.com if you need additional information or have any
.\" questions.
.\"
.\" Automatically generated by Pandoc 2.3.1
.\"
! .TH "JAVA" "1" "2019" "JDK 13" "JDK Commands"
.hy
.SH NAME
.PP
java \- launch a Java application
.SH SYNOPSIS
--- 20,30 ----
.\" or visit www.oracle.com if you need additional information or have any
.\" questions.
.\"
.\" Automatically generated by Pandoc 2.3.1
.\"
! .TH "JAVA" "1" "2020" "JDK 14" "JDK Commands"
.hy
.SH NAME
.PP
java \- launch a Java application
.SH SYNOPSIS
*** 179,190 ****
\f[B]Note:\f[R] The valid values of \f[I]N\f[R] change for each release,
with new values added and old values removed.
You\[aq]ll get an error message if you use a value of \f[I]N\f[R] that is
no longer supported.
Supported values of \f[I]N\f[R] for this release are \f[CB]7\f[R],
! \f[CB]8\f[R], \f[CB]9\f[R], \f[CB]10\f[R], \f[CB]11\f[R], \f[CB]12\f[R], and
! \f[CB]13\f[R].
.RE
.PP
If the file does not have the \f[CB]\&.java\f[R] extension, the
\f[CB]\-\-source\f[R] option must be used to tell the \f[CB]java\f[R]
command to use the source\-file mode.
--- 179,190 ----
\f[B]Note:\f[R] The valid values of \f[I]N\f[R] change for each release,
with new values added and old values removed.
You\[aq]ll get an error message if you use a value of \f[I]N\f[R] that is
no longer supported.
Supported values of \f[I]N\f[R] for this release are \f[CB]7\f[R],
! \f[CB]8\f[R], \f[CB]9\f[R], \f[CB]10\f[R], \f[CB]11\f[R], \f[CB]12\f[R],
! \f[CB]13\f[R], and \f[CB]14\f[R].
.RE
.PP
If the file does not have the \f[CB]\&.java\f[R] extension, the
\f[CB]\-\-source\f[R] option must be used to tell the \f[CB]java\f[R]
command to use the source\-file mode.
*** 265,275 ****
.IP \[bu] 2
The source file should contain one or more top\-level classes, the first
of which is taken as the class to be executed.
.IP \[bu] 2
The compiler does not enforce the optional restriction defined at the
! end of JLS §7.6, that a type in a named package should exist in a file
whose name is composed from the type name followed by the
\f[CB]\&.java\f[R] extension.
.IP \[bu] 2
If the source file contains errors, appropriate error messages are
written to the standard error stream, and the launcher exits with a
--- 265,275 ----
.IP \[bu] 2
The source file should contain one or more top\-level classes, the first
of which is taken as the class to be executed.
.IP \[bu] 2
The compiler does not enforce the optional restriction defined at the
! end of JLS ??7.6, that a type in a named package should exist in a file
whose name is composed from the type name followed by the
\f[CB]\&.java\f[R] extension.
.IP \[bu] 2
If the source file contains errors, appropriate error messages are
written to the standard error stream, and the launcher exits with a
*** 313,323 ****
\f[CB]java\f[R] command line on the system.
\f[CB]JDK_JAVA_OPTIONS\f[R] environment variable content is treated in the
same manner as that specified in the command line.
.PP
Single (\f[CB]\[aq]\f[R]) or double (\f[CB]"\f[R]) quotes can be used to
! enclose arguments that\ contain whitespace characters.
All content between the open quote and the first matching close quote
are preserved by simply removing the pair of quotes.
In case a matching quote is not found, the launcher will abort with an
error message.
\f[CB]\@\f[R]\-files are supported as they are specified in the command
--- 313,323 ----
\f[CB]java\f[R] command line on the system.
\f[CB]JDK_JAVA_OPTIONS\f[R] environment variable content is treated in the
same manner as that specified in the command line.
.PP
Single (\f[CB]\[aq]\f[R]) or double (\f[CB]"\f[R]) quotes can be used to
! enclose arguments that contain whitespace characters.
All content between the open quote and the first matching close quote
are preserved by simply removing the pair of quotes.
In case a matching quote is not found, the launcher will abort with an
error message.
\f[CB]\@\f[R]\-files are supported as they are specified in the command
*** 800,823 ****
the JVM terminates with an irrecoverable error in such cases.
Expect a performance degradation when this option is used.
.RS
.RE
.TP
- .B \f[CB]\-Xcomp\f[R]
- Forces compilation of methods on first invocation.
- By default, the Client VM (\f[CB]\-client\f[R]) performs 1,000 interpreted
- method invocations and the Server VM (\f[CB]\-server\f[R]) performs 10,000
- interpreted method invocations to gather information for efficient
- compilation.
- Specifying the \f[CB]\-Xcomp\f[R] option disables interpreted method
- invocations to increase compilation performance at the expense of
- efficiency.
- You can also change the number of interpreted method invocations before
- compilation using the \f[CB]\-XX:CompileThreshold\f[R] option.
- .RS
- .RE
- .TP
.B \f[CB]\-Xdebug\f[R]
Does nothing.
Provided for backward compatibility.
.RS
.RE
--- 800,809 ----
*** 850,859 ****
--- 836,847 ----
.RE
.TP
.B \f[CB]\-Xmixed\f[R]
Executes all bytecode by the interpreter except for hot methods, which
are compiled to native code.
+ On by default.
+ Use \f[CB]\-Xint\f[R] to switch off.
.RS
.RE
.TP
.B \f[CB]\-Xmn\f[R] \f[I]size\f[R]
Sets the initial and maximum size (in bytes) of the heap for the young
*** 1641,1651 ****
.B \f[CB]\-XX:+PreserveFramePointer\f[R]
Selects between using the RBP register as a general purpose register
(\f[CB]\-XX:\-PreserveFramePointer\f[R]) and using the RBP register to
hold the frame pointer of the currently executing method
(\f[CB]\-XX:+PreserveFramePointer\f[R] .
! If the frame pointer is available, then external profiling tools\ (for
example, Linux perf) can construct more accurate stack traces.
.RS
.RE
.TP
.B \f[CB]\-XX:+PrintNMTStatistics\f[R]
--- 1629,1639 ----
.B \f[CB]\-XX:+PreserveFramePointer\f[R]
Selects between using the RBP register as a general purpose register
(\f[CB]\-XX:\-PreserveFramePointer\f[R]) and using the RBP register to
hold the frame pointer of the currently executing method
(\f[CB]\-XX:+PreserveFramePointer\f[R] .
! If the frame pointer is available, then external profiling tools (for
example, Linux perf) can construct more accurate stack traces.
.RS
.RE
.TP
.B \f[CB]\-XX:+PrintNMTStatistics\f[R]
*** 1692,1701 ****
--- 1680,1702 ----
bootstrap class paths.
.PP
See \f[B]Application Class Data Sharing\f[R].
.RE
.TP
+ .B \f[CB]\-XX:+ShowCodeDetailsInExceptionMessages\f[R]
+ Enables printing of improved \f[CB]NullPointerException\f[R] messages.
+ When an application throws a \f[CB]NullPointerException\f[R], the option
+ enables the JVM to analyze the program\[aq]s bytecode instructions to
+ determine precisely which reference is \f[CB]null\f[R], and describes the
+ source with a null\-detail message.
+ The null\-detail message is calculated and returned by
+ \f[CB]NullPointerException.getMessage()\f[R], and will be printed as the
+ exception message along with the method, filename, and line number.
+ By default, this option is disabled.
+ .RS
+ .RE
+ .TP
.B \f[CB]\-XX:+ShowMessageBoxOnError\f[R]
Enables the display of a dialog box when the JVM experiences an
irrecoverable error.
This prevents the JVM from exiting and keeps the process active so that
you can attach a debugger to it to investigate the cause of the error.
*** 1828,1838 ****
.TP
.B \f[CB]\-XX:ThreadStackSize=\f[R]\f[I]size\f[R]
Sets the Java thread stack size (in kilobytes).
Use of a scaling suffix, such as \f[CB]k\f[R], results in the scaling of
the kilobytes value so that \f[CB]\-XX:ThreadStackSize=1k\f[R] sets the
! Java thread stack size\ to 1024*1024 bytes or 1 megabyte.
The default value depends on the platform:
.RS
.IP \[bu] 2
Linux/x64 (64\-bit): 1024 KB
.IP \[bu] 2
--- 1829,1839 ----
.TP
.B \f[CB]\-XX:ThreadStackSize=\f[R]\f[I]size\f[R]
Sets the Java thread stack size (in kilobytes).
Use of a scaling suffix, such as \f[CB]k\f[R], results in the scaling of
the kilobytes value so that \f[CB]\-XX:ThreadStackSize=1k\f[R] sets the
! Java thread stack size to 1024*1024 bytes or 1 megabyte.
The default value depends on the platform:
.RS
.IP \[bu] 2
Linux/x64 (64\-bit): 1024 KB
.IP \[bu] 2
*** 1890,1902 ****
The VM now provides automatic container detection support, which allows
the VM to determine the amount of memory and number of processors that
are available to a Java process running in docker containers.
It uses this information to allocate system resources.
This support is only available on Linux x64 platforms.
! \ If supported, the default for this flag is\ \f[CB]true\f[R], and
! container support is enabled by default.
! \ It\ can be disabled with\ \f[CB]\-XX:\-UseContainerSupport\f[R].
.RS
.PP
Unified Logging is available to help to diagnose issues related to this
support.
.PP
--- 1891,1903 ----
The VM now provides automatic container detection support, which allows
the VM to determine the amount of memory and number of processors that
are available to a Java process running in docker containers.
It uses this information to allocate system resources.
This support is only available on Linux x64 platforms.
! If supported, the default for this flag is \f[CB]true\f[R], and container
! support is enabled by default.
! It can be disabled with \f[CB]\-XX:\-UseContainerSupport\f[R].
.RS
.PP
Unified Logging is available to help to diagnose issues related to this
support.
.PP
*** 1962,1973 ****
.RS
.RS
.PP
\f[CB]\-XX:AllocateInstancePrefetchLines=1\f[R]
.RE
- .PP
- Only the Java HotSpot Server VM supports this option.
.RE
.TP
.B \f[CB]\-XX:AllocatePrefetchDistance=\f[R]\f[I]size\f[R]
Sets the size (in bytes) of the prefetch distance for object allocation.
Memory about to be written with the value of new objects is prefetched
--- 1963,1972 ----
*** 1988,2015 ****
bytes:
.RS
.PP
\f[CB]\-XX:AllocatePrefetchDistance=1024\f[R]
.RE
- .PP
- Only the Java HotSpot Server VM supports this option.
.RE
.TP
.B \f[CB]\-XX:AllocatePrefetchInstr=\f[R]\f[I]instruction\f[R]
Sets the prefetch instruction to prefetch ahead of the allocation
pointer.
- Only the Java HotSpot Server VM supports this option.
Possible values are from 0 to 3.
The actual instructions behind the values depend on the platform.
By default, the prefetch instruction is set to 0:
.RS
.RS
.PP
\f[CB]\-XX:AllocatePrefetchInstr=0\f[R]
.RE
- .PP
- Only the Java HotSpot Server VM supports this option.
.RE
.TP
.B \f[CB]\-XX:AllocatePrefetchLines=\f[R]\f[I]lines\f[R]
Sets the number of cache lines to load after the last object allocation
by using the prefetch instructions generated in compiled code.
--- 1987,2009 ----
*** 2021,2032 ****
to 5:
.RS
.PP
\f[CB]\-XX:AllocatePrefetchLines=5\f[R]
.RE
- .PP
- Only the Java HotSpot Server VM supports this option.
.RE
.TP
.B \f[CB]\-XX:AllocatePrefetchStepSize=\f[R]\f[I]size\f[R]
Sets the step size (in bytes) for sequential prefetch instructions.
Append the letter \f[CB]k\f[R] or \f[CB]K\f[R] to indicate kilobytes,
--- 2015,2024 ----
*** 2036,2047 ****
.RS
.RS
.PP
\f[CB]\-XX:AllocatePrefetchStepSize=16\f[R]
.RE
- .PP
- Only the Java HotSpot Server VM supports this option.
.RE
.TP
.B \f[CB]\-XX:AllocatePrefetchStyle=\f[R]\f[I]style\f[R]
Sets the generated code style for prefetch instructions.
The \f[I]style\f[R] argument is an integer from 0 to 3:
--- 2028,2037 ----
*** 2052,2077 ****
.RS
.RE
.TP
.B \f[CB]1\f[R]
Execute prefetch instructions after each allocation.
! This is the default parameter.
.RS
.RE
.TP
.B \f[CB]2\f[R]
Use the thread\-local allocation block (TLAB) watermark pointer to
determine when prefetch instructions are executed.
.RS
.RE
.TP
.B \f[CB]3\f[R]
! Use BIS instruction on SPARC for allocation prefetch.
.RS
.RE
- .PP
- Only the Java HotSpot Server VM supports this option.
.RE
.TP
.B \f[CB]\-XX:+BackgroundCompilation\f[R]
Enables background compilation.
This option is enabled by default.
--- 2042,2065 ----
.RS
.RE
.TP
.B \f[CB]1\f[R]
Execute prefetch instructions after each allocation.
! This is the default setting.
.RS
.RE
.TP
.B \f[CB]2\f[R]
Use the thread\-local allocation block (TLAB) watermark pointer to
determine when prefetch instructions are executed.
.RS
.RE
.TP
.B \f[CB]3\f[R]
! Generate one prefetch instruction per cache line.
.RS
.RE
.RE
.TP
.B \f[CB]\-XX:+BackgroundCompilation\f[R]
Enables background compilation.
This option is enabled by default.
*** 2081,2101 ****
.RS
.RE
.TP
.B \f[CB]\-XX:CICompilerCount=\f[R]\f[I]threads\f[R]
Sets the number of compiler threads to use for compilation.
! By default, the number of threads is set to 2 for the server JVM, to 1
! for the client JVM, and it scales to the number of cores if tiered
! compilation is used.
The following example shows how to set the number of threads to 2:
.RS
.RS
.PP
\f[CB]\-XX:CICompilerCount=2\f[R]
.RE
.RE
.TP
.B \f[CB]\-XX:CompileCommand=\f[R]\f[I]command\f[R]\f[CB],\f[R]\f[I]method\f[R][\f[CB],\f[R]\f[I]option\f[R]]
Specifies a \f[I]command\f[R] to perform on a \f[I]method\f[R].
For example, to exclude the \f[CB]indexOf()\f[R] method of the
\f[CB]String\f[R] class from being compiled, use the following:
.RS
--- 2069,2095 ----
.RS
.RE
.TP
.B \f[CB]\-XX:CICompilerCount=\f[R]\f[I]threads\f[R]
Sets the number of compiler threads to use for compilation.
! By default, the number of compiler threads is selected automatically
! depending on the number of CPUs and memory available for compiled code.
The following example shows how to set the number of threads to 2:
.RS
.RS
.PP
\f[CB]\-XX:CICompilerCount=2\f[R]
.RE
.RE
.TP
+ .B \f[CB]\-XX:+UseDynamicNumberOfCompilerThreads\f[R]
+ Dynamically create compiler thread up to the limit specified by
+ \f[CB]\-XX:CICompilerCount\f[R].
+ This option is enabled by default.
+ .RS
+ .RE
+ .TP
.B \f[CB]\-XX:CompileCommand=\f[R]\f[I]command\f[R]\f[CB],\f[R]\f[I]method\f[R][\f[CB],\f[R]\f[I]option\f[R]]
Specifies a \f[I]command\f[R] to perform on a \f[I]method\f[R].
For example, to exclude the \f[CB]indexOf()\f[R] method of the
\f[CB]String\f[R] class from being compiled, use the following:
.RS
*** 2316,2352 ****
\-XX:CompileOnly=.length
\f[R]
.fi
.RE
.TP
- .B \f[CB]\-XX:CompileThreshold=\f[R]\f[I]invocations\f[R]
- Sets the number of interpreted method invocations before compilation.
- By default, in the server JVM, the JIT compiler performs 10,000
- interpreted method invocations to gather information for efficient
- compilation.
- For the client JVM, the default setting is 1,500 invocations.
- This option is ignored when tiered compilation is enabled; see the
- option \f[CB]\-XX:\-TieredCompilation\f[R].
- The following example shows how to set the number of interpreted method
- invocations to 5,000:
- .RS
- .RS
- .PP
- \f[CB]\-XX:CompileThreshold=5000\f[R]
- .RE
- .PP
- You can completely disable interpretation of Java methods before
- compilation by specifying the \f[CB]\-Xcomp\f[R] option.
- .RE
- .TP
.B \f[CB]\-XX:CompileThresholdScaling=\f[R]\f[I]scale\f[R]
Provides unified control of first compilation.
This option controls when methods are first compiled for both the tiered
and the nontiered modes of operation.
! The \f[CB]CompileThresholdScaling\f[R] option has an integer value between
! 0 and +Inf and scales the thresholds corresponding to the current mode
! of operation (both tiered and nontiered).
Setting \f[CB]CompileThresholdScaling\f[R] to a value less than 1.0
results in earlier compilation while values greater than 1.0 delay
compilation.
Setting \f[CB]CompileThresholdScaling\f[R] to 0 is equivalent to disabling
compilation.
--- 2310,2326 ----
\-XX:CompileOnly=.length
\f[R]
.fi
.RE
.TP
.B \f[CB]\-XX:CompileThresholdScaling=\f[R]\f[I]scale\f[R]
Provides unified control of first compilation.
This option controls when methods are first compiled for both the tiered
and the nontiered modes of operation.
! The \f[CB]CompileThresholdScaling\f[R] option has a floating point value
! between 0 and +Inf and scales the thresholds corresponding to the
! current mode of operation (both tiered and nontiered).
Setting \f[CB]CompileThresholdScaling\f[R] to a value less than 1.0
results in earlier compilation while values greater than 1.0 delay
compilation.
Setting \f[CB]CompileThresholdScaling\f[R] to 0 is equivalent to disabling
compilation.
*** 2356,2375 ****
.B \f[CB]\-XX:+DoEscapeAnalysis\f[R]
Enables the use of escape analysis.
This option is enabled by default.
To disable the use of escape analysis, specify
\f[CB]\-XX:\-DoEscapeAnalysis\f[R].
- Only the Java HotSpot Server VM supports this option.
.RS
.RE
.TP
.B \f[CB]\-XX:InitialCodeCacheSize=\f[R]\f[I]size\f[R]
Sets the initial code cache size (in bytes).
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 set to 500 KB.
The initial code cache size shouldn\[aq]t be less than the system\[aq]s
minimal memory page size.
The following example shows how to set the initial code cache size to 32
KB:
.RS
--- 2330,2348 ----
.B \f[CB]\-XX:+DoEscapeAnalysis\f[R]
Enables the use of escape analysis.
This option is enabled by default.
To disable the use of escape analysis, specify
\f[CB]\-XX:\-DoEscapeAnalysis\f[R].
.RS
.RE
.TP
.B \f[CB]\-XX:InitialCodeCacheSize=\f[R]\f[I]size\f[R]
Sets the initial code cache size (in bytes).
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 depends on the platform.
The initial code cache size shouldn\[aq]t be less than the system\[aq]s
minimal memory page size.
The following example shows how to set the initial code cache size to 32
KB:
.RS
*** 2385,2402 ****
To disable method inlining, specify \f[CB]\-XX:\-Inline\f[R].
.RS
.RE
.TP
.B \f[CB]\-XX:InlineSmallCode=\f[R]\f[I]size\f[R]
! Sets the maximum code size (in bytes) for compiled methods that should
! be inlined.
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.
! Only compiled methods with the size smaller than the specified size is
! inlined.
! By default, the maximum code size is set to 1000 bytes:
.RS
.RS
.PP
\f[CB]\-XX:InlineSmallCode=1000\f[R]
.RE
--- 2358,2375 ----
To disable method inlining, specify \f[CB]\-XX:\-Inline\f[R].
.RS
.RE
.TP
.B \f[CB]\-XX:InlineSmallCode=\f[R]\f[I]size\f[R]
! Sets the maximum code size (in bytes) for already compiled methods that
! may be inlined.
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 depends on the platform and on whether tiered
! compilation is enabled.
! In the following example it is set to 1000 bytes:
.RS
.RS
.PP
\f[CB]\-XX:InlineSmallCode=1000\f[R]
.RE
*** 2418,2429 ****
You can enable verbose diagnostic output with a message printed to the
console every time a method is compiled by using the
\f[CB]\-XX:+PrintCompilation\f[R] option.
.RE
.TP
.B \f[CB]\-XX:MaxInlineSize=\f[R]\f[I]size\f[R]
! Sets the maximum bytecode size (in bytes) of a method to be inlined.
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.
By default, the maximum bytecode size is set to 35 bytes:
.RS
--- 2391,2417 ----
You can enable verbose diagnostic output with a message printed to the
console every time a method is compiled by using the
\f[CB]\-XX:+PrintCompilation\f[R] option.
.RE
.TP
+ .B \f[CB]\-XX:FreqInlineSize=\f[R]\f[I]size\f[R]
+ Sets the maximum bytecode size (in bytes) of a hot method to be inlined.
+ 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 depends on the platform.
+ In the following example it is set to 325 bytes:
+ .RS
+ .RS
+ .PP
+ \f[CB]\-XX:FreqInlineSize=325\f[R]
+ .RE
+ .RE
+ .TP
.B \f[CB]\-XX:MaxInlineSize=\f[R]\f[I]size\f[R]
! Sets the maximum bytecode size (in bytes) of a cold method to be
! inlined.
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.
By default, the maximum bytecode size is set to 35 bytes:
.RS
*** 2431,2448 ****
.PP
\f[CB]\-XX:MaxInlineSize=35\f[R]
.RE
.RE
.TP
.B \f[CB]\-XX:MaxNodeLimit=\f[R]\f[I]nodes\f[R]
Sets the maximum number of nodes to be used during single method
compilation.
! By default, the maximum number of nodes is set to 65,000:
.RS
.RS
.PP
! \f[CB]\-XX:MaxNodeLimit=65000\f[R]
.RE
.RE
.TP
.B \f[CB]\-XX:NonNMethodCodeHeapSize=\f[R]\f[I]size\f[R]
Sets the size in bytes of the code segment containing nonmethod code.
--- 2419,2452 ----
.PP
\f[CB]\-XX:MaxInlineSize=35\f[R]
.RE
.RE
.TP
+ .B \f[CB]\-XX:MaxTrivialSize=\f[R]\f[I]size\f[R]
+ Sets the maximum bytecode size (in bytes) of a trivial method to be
+ inlined.
+ 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.
+ By default, the maximum bytecode size of a trivial method is set to 6
+ bytes:
+ .RS
+ .RS
+ .PP
+ \f[CB]\-XX:MaxTrivialSize=6\f[R]
+ .RE
+ .RE
+ .TP
.B \f[CB]\-XX:MaxNodeLimit=\f[R]\f[I]nodes\f[R]
Sets the maximum number of nodes to be used during single method
compilation.
! By default the value depends on the features enabled.
! In the following example the maximum number of nodes is set to 100,000:
.RS
.RS
.PP
! \f[CB]\-XX:MaxNodeLimit=100000\f[R]
.RE
.RE
.TP
.B \f[CB]\-XX:NonNMethodCodeHeapSize=\f[R]\f[I]size\f[R]
Sets the size in bytes of the code segment containing nonmethod code.
*** 2459,2489 ****
methods.
This flag is used only if \f[CB]\-XX:SegmentedCodeCache\f[R] is enabled.
.RS
.RE
.TP
- .B \f[CB]\-XX:MaxTrivialSize=\f[R]\f[I]size\f[R]
- Sets the maximum bytecode size (in bytes) of a trivial method to be
- inlined.
- 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.
- By default, the maximum bytecode size of a trivial method is set to 6
- bytes:
- .RS
- .RS
- .PP
- \f[CB]\-XX:MaxTrivialSize=6\f[R]
- .RE
- .RE
- .TP
.B \f[CB]\-XX:+OptimizeStringConcat\f[R]
Enables the optimization of \f[CB]String\f[R] concatenation operations.
This option is enabled by default.
To disable the optimization of \f[CB]String\f[R] concatenation operations,
specify \f[CB]\-XX:\-OptimizeStringConcat\f[R].
- Only the Java HotSpot Server VM supports this option.
.RS
.RE
.TP
.B \f[CB]\-XX:+PrintAssembly\f[R]
Enables printing of assembly code for bytecoded and native methods by
--- 2463,2477 ----
*** 2593,2620 ****
.RE
.TP
.B \f[CB]\-XX:\-TieredCompilation\f[R]
Disables the use of tiered compilation.
By default, this option is enabled.
! Only the Java HotSpot Server VM supports this option.
.RS
.RE
.TP
.B \f[CB]\-XX:+UseAES\f[R]
! Enables hardware\-based AES intrinsics for Intel, AMD, and SPARC
! hardware.
! Intel Westmere (2010 and newer), AMD Bulldozer (2011 and newer), and
! SPARC (T4 and newer) are the supported hardware.
The \f[CB]\-XX:+UseAES\f[R] is used in conjunction with UseAESIntrinsics.
Flags that control intrinsics now require the option
\f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
.RS
.RE
.TP
.B \f[CB]\-XX:+UseAESIntrinsics\f[R]
! Enables \f[CB]\-XX:+UseAES\f[R] and \f[CB]\-XX:+UseAESIntrinsics\f[R] flags
! by default and are supported only for the Java HotSpot Server VM.
To disable hardware\-based AES intrinsics, specify
\f[CB]\-XX:\-UseAES\ \-XX:\-UseAESIntrinsics\f[R].
For example, to enable hardware AES, use the following flags:
.RS
.RS
--- 2581,2619 ----
.RE
.TP
.B \f[CB]\-XX:\-TieredCompilation\f[R]
Disables the use of tiered compilation.
By default, this option is enabled.
! .RS
! .RE
! .TP
! .B \f[CB]\-XX:UseSSE=\f[R]\f[I]version\f[R]
! Enables the use of SSE instruction set of a specified version.
! Is set by default to the highest supported version available (x86 only).
! .RS
! .RE
! .TP
! .B \f[CB]\-XX:UseAVX=\f[R]\f[I]version\f[R]
! Enables the use of AVX instruction set of a specified version.
! Is set by default to the highest supported version available (x86 only).
.RS
.RE
.TP
.B \f[CB]\-XX:+UseAES\f[R]
! Enables hardware\-based AES intrinsics for hardware that supports it.
! This option is on by default on hardware that has the necessary
! instructions.
The \f[CB]\-XX:+UseAES\f[R] is used in conjunction with UseAESIntrinsics.
Flags that control intrinsics now require the option
\f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
.RS
.RE
.TP
.B \f[CB]\-XX:+UseAESIntrinsics\f[R]
! Enables AES intrinsics.
! Specifying\f[CB]\-XX:+UseAESIntrinsics\f[R] is equivalent to also enabling
! \f[CB]\-XX:+UseAES\f[R].
To disable hardware\-based AES intrinsics, specify
\f[CB]\-XX:\-UseAES\ \-XX:\-UseAESIntrinsics\f[R].
For example, to enable hardware AES, use the following flags:
.RS
.RS
*** 2622,2634 ****
\f[CB]\-XX:+UseAES\ \-XX:+UseAESIntrinsics\f[R]
.RE
.PP
Flags that control intrinsics now require the option
\f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! To support UseAES and UseAESIntrinsics flags, use the \f[CB]\-server\f[R]
! option to select the Java HotSpot Server VM.
! These flags aren\[aq]t supported on Client VM.
.RE
.TP
.B \f[CB]\-XX:+UseCMoveUnconditionally\f[R]
Generates CMove (scalar and vector) instructions regardless of
profitability analysis.
--- 2621,2771 ----
\f[CB]\-XX:+UseAES\ \-XX:+UseAESIntrinsics\f[R]
.RE
.PP
Flags that control intrinsics now require the option
\f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .RE
! .TP
! .B \f[CB]\-XX:+UseAESCTRIntrinsics\f[R]
! Analogous to \f[CB]\-XX:+UseAESIntrinsics\f[R] enables AES/CTR intrinsics.
! .RS
! .RE
! .TP
! .B \f[CB]\-XX:+UseGHASHIntrinsics\f[R]
! Controls the use of GHASH intrinsics.
! Enabled by default on platforms that support the corresponding
! instructions.
! Flags that control intrinsics now require the option
! \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .RS
! .RE
! .TP
! .B \f[CB]\-XX:+UseBASE64Intrinsics\f[R]
! Controls the use of accelerated BASE64 encoding routines for
! \f[CB]java.util.Base64\f[R].
! Enabled by default on platforms that support it.
! Flags that control intrinsics now require the option
! \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .RS
! .RE
! .TP
! .B \f[CB]\-XX:+UseAdler32Intrinsics\f[R]
! Controls the use of Adler32 checksum algorithm intrinsic for
! \f[CB]java.util.zip.Adler32\f[R].
! Enabled by default on platforms that support it.
! Flags that control intrinsics now require the option
! \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .RS
! .RE
! .TP
! .B \f[CB]\-XX:+UseCRC32Intrinsics\f[R]
! Controls the use of CRC32 intrinsics for \f[CB]java.util.zip.CRC32\f[R].
! Enabled by default on platforms that support it.
! Flags that control intrinsics now require the option
! \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .RS
! .RE
! .TP
! .B \f[CB]\-XX:+UseCRC32CIntrinsics\f[R]
! Controls the use of CRC32C intrinsics for \f[CB]java.util.zip.CRC32C\f[R].
! Enabled by default on platforms that support it.
! Flags that control intrinsics now require the option
! \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .RS
! .RE
! .TP
! .B \f[CB]\-XX:+UseSHA\f[R]
! Enables hardware\-based intrinsics for SHA crypto hash functions for
! SPARC hardware.
! The \f[CB]UseSHA\f[R] option is used in conjunction with the
! \f[CB]UseSHA1Intrinsics\f[R], \f[CB]UseSHA256Intrinsics\f[R], and
! \f[CB]UseSHA512Intrinsics\f[R] options.
! .RS
! .PP
! The \f[CB]UseSHA\f[R] and \f[CB]UseSHA*Intrinsics\f[R] flags are enabled by
! default on machines that support the corresponding instructions.
! .PP
! This feature is applicable only when using the
! \f[CB]sun.security.provider.Sun\f[R] provider for SHA operations.
! Flags that control intrinsics now require the option
! \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .PP
! To disable all hardware\-based SHA intrinsics, specify the
! \f[CB]\-XX:\-UseSHA\f[R].
! To disable only a particular SHA intrinsic, use the appropriate
! corresponding option.
! For example: \f[CB]\-XX:\-UseSHA256Intrinsics\f[R].
! .RE
! .TP
! .B \f[CB]\-XX:+UseSHA1Intrinsics\f[R]
! Enables intrinsics for SHA\-1 crypto hash function.
! Flags that control intrinsics now require the option
! \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .RS
! .RE
! .TP
! .B \f[CB]\-XX:+UseSHA256Intrinsics\f[R]
! Enables intrinsics for SHA\-224 and SHA\-256 crypto hash functions.
! Flags that control intrinsics now require the option
! \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .RS
! .RE
! .TP
! .B \f[CB]\-XX:+UseSHA512Intrinsics\f[R]
! Enables intrinsics for SHA\-384 and SHA\-512 crypto hash functions.
! Flags that control intrinsics now require the option
! \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .RS
! .RE
! .TP
! .B \f[CB]\-XX:+UseMathExactIntrinsics\f[R]
! Enables intrinsification of various \f[CB]java.lang.Math.*Exact()\f[R]
! functions.
! Enabled by default.
! Flags that control intrinsics now require the option
! \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .RS
! .RE
! .TP
! .B \f[CB]\-XX:+UseMultiplyToLenIntrinsic\f[R]
! Enables intrinsification of \f[CB]BigInteger.multiplyToLen()\f[R].
! Enabled by default on platforms that support it.
! Flags that control intrinsics now require the option
! \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .RS
! .RE
! .TP
! .B \-XX:+UseSquareToLenIntrinsic
! Enables intrinsification of \f[CB]BigInteger.squareToLen()\f[R].
! Enabled by default on platforms that support it.
! Flags that control intrinsics now require the option
! \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .RS
! .RE
! .TP
! .B \-XX:+UseMulAddIntrinsic
! Enables intrinsification of \f[CB]BigInteger.mulAdd()\f[R].
! Enabled by default on platforms that support it.
! Flags that control intrinsics now require the option
! \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .RS
! .RE
! .TP
! .B \-XX:+UseMontgomeryMultiplyIntrinsic
! Enables intrinsification of \f[CB]BigInteger.montgomeryMultiply()\f[R].
! Enabled by default on platforms that support it.
! Flags that control intrinsics now require the option
! \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .RS
! .RE
! .TP
! .B \-XX:+UseMontgomerySquareIntrinsic
! Enables intrinsification of \f[CB]BigInteger.montgomerySquare()\f[R].
! Enabled by default on platforms that support it.
! Flags that control intrinsics now require the option
! \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
! .RS
.RE
.TP
.B \f[CB]\-XX:+UseCMoveUnconditionally\f[R]
Generates CMove (scalar and vector) instructions regardless of
profitability analysis.
*** 2648,2664 ****
table.
This option is disabled by default.
It should be used only on machines with multiple sockets, where it
increases the performance of Java applications that rely on concurrent
operations.
- Only the Java HotSpot Server VM supports this option.
.RS
.RE
.TP
.B \f[CB]\-XX:+UseCountedLoopSafepoints\f[R]
Keeps safepoints in counted loops.
! Its default value is false.\
.RS
.RE
.TP
.B \f[CB]\-XX:+UseFMA\f[R]
Enables hardware\-based FMA intrinsics for hardware where FMA
--- 2785,2819 ----
table.
This option is disabled by default.
It should be used only on machines with multiple sockets, where it
increases the performance of Java applications that rely on concurrent
operations.
.RS
.RE
.TP
.B \f[CB]\-XX:+UseCountedLoopSafepoints\f[R]
Keeps safepoints in counted loops.
! Its default value depends on whether the selected garbage collector
! requires low latency safepoints.
! .RS
! .RE
! .TP
! .B \f[CB]\-XX:LoopStripMiningIter=\f[R]\f[I]number_of_iterations\f[R]
! Controls the number of iterations in the inner strip mined loop.
! Strip mining transforms counted loops into two level nested loops.
! Safepoints are kept in the outer loop while the inner loop can execute
! at full speed.
! This option controls the maximum number of iterations in the inner loop.
! The default value is 1,000.
! .RS
! .RE
! .TP
! .B \f[CB]\-XX:LoopStripMiningIterShortLoop\f[R]=\f[I]number_of_iterations\f[R]
! Controls loop strip mining optimization.
! Loops with the number of iterations less than specified will not have
! safepoints in them.
! Default value is 1/10th of \f[CB]\-XX:LoopStripMiningIter\f[R].
.RS
.RE
.TP
.B \f[CB]\-XX:+UseFMA\f[R]
Enables hardware\-based FMA intrinsics for hardware where FMA
*** 2685,2696 ****
.B \f[CB]\-XX:+UseRTMLocking\f[R]
Generates Restricted Transactional Memory (RTM) locking code for all
inflated locks, with the normal locking mechanism as the fallback
handler.
This option is disabled by default.
! Options related to RTM are available only for the Java HotSpot Server VM
! on x86 CPUs that support Transactional Synchronization Extensions (TSX).
.RS
.PP
RTM is part of Intel\[aq]s TSX, which is an x86 instruction set
extension and facilitates the creation of multithreaded applications.
RTM introduces the new instructions \f[CB]XBEGIN\f[R], \f[CB]XABORT\f[R],
--- 2840,2851 ----
.B \f[CB]\-XX:+UseRTMLocking\f[R]
Generates Restricted Transactional Memory (RTM) locking code for all
inflated locks, with the normal locking mechanism as the fallback
handler.
This option is disabled by default.
! Options related to RTM are available only on x86 CPUs that support
! Transactional Synchronization Extensions (TSX).
.RS
.PP
RTM is part of Intel\[aq]s TSX, which is an x86 instruction set
extension and facilitates the creation of multithreaded applications.
RTM introduces the new instructions \f[CB]XBEGIN\f[R], \f[CB]XABORT\f[R],
*** 2729,2791 ****
As a result, the processors repeatedly invalidate the cache lines of
other processors, which forces them to read from main memory instead of
their cache.
.RE
.TP
- .B \f[CB]\-XX:+UseSHA\f[R]
- Enables hardware\-based intrinsics for SHA crypto hash functions for
- SPARC hardware.
- The \f[CB]UseSHA\f[R] option is used in conjunction with the
- \f[CB]UseSHA1Intrinsics\f[R], \f[CB]UseSHA256Intrinsics\f[R], and
- \f[CB]UseSHA512Intrinsics\f[R] options.
- .RS
- .PP
- The \f[CB]UseSHA\f[R] and \f[CB]UseSHA*Intrinsics\f[R] flags are enabled by
- default, and are supported only for Java HotSpot Server VM 64\-bit on
- SPARC T4 and newer.
- .PP
- This feature is applicable only when using the
- \f[CB]sun.security.provider.Sun\f[R] provider for SHA operations.
- Flags that control intrinsics now require the option
- \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
- .PP
- To disable all hardware\-based SHA intrinsics, specify the
- \f[CB]\-XX:\-UseSHA\f[R].
- To disable only a particular SHA intrinsic, use the appropriate
- corresponding option.
- For example: \f[CB]\-XX:\-UseSHA256Intrinsics\f[R].
- .RE
- .TP
- .B \f[CB]\-XX:+UseSHA1Intrinsics\f[R]
- Enables intrinsics for SHA\-1 crypto hash function.
- Flags that control intrinsics now require the option
- \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
- .RS
- .RE
- .TP
- .B \f[CB]\-XX:+UseSHA256Intrinsics\f[R]
- Enables intrinsics for SHA\-224 and SHA\-256 crypto hash functions.
- Flags that control intrinsics now require the option
- \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
- .RS
- .RE
- .TP
- .B \f[CB]\-XX:+UseSHA512Intrinsics\f[R]
- Enables intrinsics for SHA\-384 and SHA\-512 crypto hash functions.
- Flags that control intrinsics now require the option
- \f[CB]\-XX:+UnlockDiagnosticVMOptions\f[R].
- .RS
- .RE
- .TP
.B \f[CB]\-XX:+UseSuperWord\f[R]
Enables the transformation of scalar operations into superword
operations.
Superword is a vectorization optimization.
This option is enabled by default.
To disable the transformation of scalar operations into superword
operations, specify \f[CB]\-XX:\-UseSuperWord\f[R].
- Only the Java HotSpot Server VM supports this option.
.RS
.RE
.SH ADVANCED SERVICEABILITY OPTIONS FOR JAVA
.PP
These \f[CB]java\f[R] options provide the ability to gather system
--- 2884,2900 ----
*** 2973,2983 ****
application.
By default, this option is disabled and all pages are committed as the
application uses the heap space.
.RS
.RE
- .RE
.TP
.B \f[CB]\-XX:ConcGCThreads=\f[R]\f[I]threads\f[R]
Sets the number of threads used for concurrent GC.
Sets \f[I]\f[CI]threads\f[I]\f[R] to approximately 1/4 of the number of
parallel garbage collection threads.
--- 3082,3091 ----
*** 3705,3722 ****
By default, this option is disabled and the default collector is used.
If it\[aq]s enabled, then the \f[CB]\-XX:+UseParallelOldGC\f[R] option is
automatically enabled, unless you explicitly disable it.
.RE
.TP
- .B \f[CB]\-XX:+UseParallelOldGC\f[R]
- Enables the use of the parallel garbage collector for full GCs.
- By default, this option is disabled.
- Enabling it automatically enables the \f[CB]\-XX:+UseParallelGC\f[R]
- option.
- .RS
- .RE
- .TP
.B \f[CB]\-XX:+UseSerialGC\f[R]
Enables the use of the serial garbage collector.
This is generally the best choice for small and simple applications that
don\[aq]t require any special functionality from garbage collection.
By default, this option is disabled and the default collector is used.
--- 3813,3822 ----
*** 3797,3815 ****
Example:
.PP
\f[CB]\-Xlog:gc:garbage\-collection.log\f[R]
.RE
.TP
- .B \f[CB]\-XX:+FailOverToOldVerifier\f[R]
- Enables automatic failover to the old verifier when the new type checker
- fails.
- By default, this option is disabled and it\[aq]s ignored (that is,
- treated as disabled) for classes with a recent bytecode version.
- 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
--- 3897,3906 ----
*** 3900,3909 ****
--- 3991,4021 ----
The replacement Unified Logging syntax is
\f[CB]\-Xlog:class+loader+constraints=info\f[R].
See \f[B]Enable Logging with the JVM Unified Logging Framework\f[R].
.RE
.TP
+ .B \f[CB]\-XX:+UseParallelOldGC\f[R]
+ Enables the use of the parallel garbage collector for full GCs.
+ By default, this option is disabled.
+ Enabling it automatically enables the \f[CB]\-XX:+UseParallelGC\f[R]
+ option.
+ .RS
+ .RE
+ .SH OBSOLETE JAVA OPTIONS
+ .PP
+ These \f[CB]java\f[R] options are still accepted but ignored, and a
+ warning is issued when they\[aq]re used.
+ .TP
+ .B \f[CB]\-XX:+FailOverToOldVerifier\f[R]
+ Enables automatic failover to the old verifier when the new type checker
+ fails.
+ By default, this option is disabled and it\[aq]s ignored (that is,
+ treated as disabled) for classes with a recent bytecode version.
+ You can enable it only for classes with older versions of the bytecode.
+ .RS
+ .RE
+ .TP
.B \f[CB]\-XX:+UseMembar\f[R]
Enabled issuing membars on thread\-state transitions.
This option was disabled by default on all platforms except ARM servers,
where it was enabled.
.RS
*** 3923,3949 ****
\f[CB]\-XX:MetaspaceSize\f[R] option.
.RS
.RE
.SH REMOVED JAVA OPTIONS
.PP
! These \f[CB]java\f[R] options have been removed in JDK 13 and using them
! results in an error of:
! .RS
! .PP
! \f[CB]Unrecognized\ VM\ option\f[R] \f[I]option\-name\f[R]
! .RE
! .TP
! .B \f[CB]\-XX:+AggressiveOpts\f[R]
! Enabled the use of aggressive performance optimization features.
! By default, this option was disabled and experimental performance
! features were not used.
! .RS
! .RE
.PP
For the lists and descriptions of options removed in previous releases
see the \f[I]Removed Java Options\f[R] section in:
.IP \[bu] 2
\f[B]Java Platform, Standard Edition Tools Reference, Release 12\f[R]
[https://docs.oracle.com/en/java/javase/12/tools/java.html#GUID\-3B1CE181\-CD30\-4178\-9602\-230B800D4FAE]
.IP \[bu] 2
\f[B]Java Platform, Standard Edition Tools Reference, Release 11\f[R]
[https://docs.oracle.com/en/java/javase/11/tools/java.html#GUID\-741FC470\-AA3E\-494A\-8D2B\-1B1FE4A990D1]
--- 4035,4052 ----
\f[CB]\-XX:MetaspaceSize\f[R] option.
.RS
.RE
.SH REMOVED JAVA OPTIONS
.PP
! No documented \f[CB]java\f[R] options have been removed in JDK 14.
.PP
For the lists and descriptions of options removed in previous releases
see the \f[I]Removed Java Options\f[R] section in:
.IP \[bu] 2
+ \f[B]Java Platform, Standard Edition Tools Reference, Release 13\f[R]
+ [https://docs.oracle.com/en/java/javase/13/docs/specs/man/java.html]
+ .IP \[bu] 2
\f[B]Java Platform, Standard Edition Tools Reference, Release 12\f[R]
[https://docs.oracle.com/en/java/javase/12/tools/java.html#GUID\-3B1CE181\-CD30\-4178\-9602\-230B800D4FAE]
.IP \[bu] 2
\f[B]Java Platform, Standard Edition Tools Reference, Release 11\f[R]
[https://docs.oracle.com/en/java/javase/11/tools/java.html#GUID\-741FC470\-AA3E\-494A\-8D2B\-1B1FE4A990D1]
*** 4010,4020 ****
entirety.
.IP \[bu] 2
A string within quotation marks may contain the characters \f[CB]\\n\f[R],
\f[CB]\\r\f[R], \f[CB]\\t\f[R], and \f[CB]\\f\f[R].
They are converted to their respective ASCII codes.
- \
.IP \[bu] 2
If a file name contains embedded spaces, then put the whole file name in
double quotation marks.
.IP \[bu] 2
File names in an argument file are relative to the current directory,
--- 4113,4122 ----
*** 4030,4044 ****
arguments are presented to the launcher literally).
.IP \[bu] 2
Lines may be continued using the continuation character (\f[CB]\\\f[R]) at
the end\-of\-line.
The two lines are concatenated with the leading white spaces trimmed.
! To prevent trimming the \ leading white spaces, a continuation character
(\f[CB]\\\f[R]) may be placed at the first column.
.IP \[bu] 2
! Because backslash (\\) is an escape character, a backslash
! character\ must be escaped with another backslash character.
.IP \[bu] 2
Partial quote is allowed and is closed by an end\-of\-file.
.IP \[bu] 2
An open quote stops at end\-of\-line unless \f[CB]\\\f[R] is the last
character, which then joins the next line by removing all leading white
--- 4132,4146 ----
arguments are presented to the launcher literally).
.IP \[bu] 2
Lines may be continued using the continuation character (\f[CB]\\\f[R]) at
the end\-of\-line.
The two lines are concatenated with the leading white spaces trimmed.
! To prevent trimming the leading white spaces, a continuation character
(\f[CB]\\\f[R]) may be placed at the first column.
.IP \[bu] 2
! Because backslash (\\) is an escape character, a backslash character
! must be escaped with another backslash character.
.IP \[bu] 2
Partial quote is allowed and is closed by an end\-of\-file.
.IP \[bu] 2
An open quote stops at end\-of\-line unless \f[CB]\\\f[R] is the last
character, which then joins the next line by removing all leading white
*** 4065,4075 ****
this is interpreted as:
.RS
.PP
\f[CB]\-cp\ lib/cool/app/jars\f[R]
.RE
! .SS Example of a Backslash Character\ Escaped with Another Backslash
Character in an Argument File
.PP
To output the following:
.RS
.PP
--- 4167,4177 ----
this is interpreted as:
.RS
.PP
\f[CB]\-cp\ lib/cool/app/jars\f[R]
.RE
! .SS Example of a Backslash Character Escaped with Another Backslash
Character in an Argument File
.PP
To output the following:
.RS
.PP
*** 4077,4087 ****
.RE
.PP
The backslash character must be specified in the argument file as:
.RS
.PP
! \f[CB]\-cp\ \ "c:\\\\Program\ Files\ (x86)\\\\Java\\\\jre\\\\lib\\\\ext;c:\\\\Program\ Files\\\\Java\\\\jre9\\\\lib\\\\ext"\f[R]
.RE
.SS Example of an EOL Escape Used to Force Concatenation of Lines in an
Argument File
.PP
In the argument file,
--- 4179,4189 ----
.RE
.PP
The backslash character must be specified in the argument file as:
.RS
.PP
! \f[CB]\-cp\ "c:\\\\Program\ Files\ (x86)\\\\Java\\\\jre\\\\lib\\\\ext;c:\\\\Program\ Files\\\\Java\\\\jre9\\\\lib\\\\ext"\f[R]
.RE
.SS Example of an EOL Escape Used to Force Concatenation of Lines in an
Argument File
.PP
In the argument file,
*** 4103,4113 ****
In the argument file,
.IP
.nf
\f[CB]
\-cp\ "/lib/cool\\
! \\app/jars”
\f[R]
.fi
.PP
This is interpreted as:
.PP
--- 4205,4215 ----
In the argument file,
.IP
.nf
\f[CB]
\-cp\ "/lib/cool\\
! \\app/jars???
\f[R]
.fi
.PP
This is interpreted as:
.PP
*** 4892,4905 ****
For example, if a flag violates a range or a constraint check, then the
JVM exits with an error:
.IP
.nf
\f[CB]
! java\ \-XX:AllocatePrefetchStyle=5\ \-version\ \ \
! intx\ AllocatePrefetchStyle=5\ is\ outside\ the\ allowed\ range\ [\ 0\ ...\ 3\ ]\ \ \
! Improperly\ specified\ VM\ option\ \[aq]AllocatePrefetchStyle=5\[aq]\ \ \
! Error:\ Could\ not\ create\ the\ Java\ Virtual\ Machine.\ \
Error:\ A\ fatal\ exception\ has\ occurred.\ Program\ will\ exit.
\f[R]
.fi
.PP
The flag \f[CB]\-XX:+PrintFlagsRanges\f[R] prints the range of all the
--- 4994,5007 ----
For example, if a flag violates a range or a constraint check, then the
JVM exits with an error:
.IP
.nf
\f[CB]
! java\ \-XX:AllocatePrefetchStyle=5\ \-version
! intx\ AllocatePrefetchStyle=5\ is\ outside\ the\ allowed\ range\ [\ 0\ ...\ 3\ ]
! Improperly\ specified\ VM\ option\ \[aq]AllocatePrefetchStyle=5\[aq]
! Error:\ Could\ not\ create\ the\ Java\ Virtual\ Machine.
Error:\ A\ fatal\ exception\ has\ occurred.\ Program\ will\ exit.
\f[R]
.fi
.PP
The flag \f[CB]\-XX:+PrintFlagsRanges\f[R] prints the range of all the
*** 5569,5590 ****
.RS
.PP
\f[CB]\-XX:SharedArchiveConfigFile=\f[R]\f[I]shared_config_file\f[R]
.RE
.PP
! JDK 9 and later supports adding both symbols and\ string objects to an
! archive for memory sharing\ when you have multiple JVM processes running
on the same host.
An example of this is having multiple JVM processes that use the same
set of Java EE classes.
When these common classes are loaded and used, new symbols and strings
may be created and added to the JVM\[aq]s internal "symbol" and "string"
! tables.\ At runtime, the symbols or string objects mapped from the
! archive file can be shared across multiple JVM processes, resulting in a
! reduction of overall memory usage.\ In addition, archiving strings also
! provides added performance benefits in both startup time and runtime
! execution.
.PP
In JDK 10 and later, CONSTANT_String entries in archived classes are
resolved to interned String objects at dump time, and all interned
String objects are archived.
However, even though all CONSTANT_String literals in all archived
--- 5671,5693 ----
.RS
.PP
\f[CB]\-XX:SharedArchiveConfigFile=\f[R]\f[I]shared_config_file\f[R]
.RE
.PP
! JDK 9 and later supports adding both symbols and string objects to an
! archive for memory sharing when you have multiple JVM processes running
on the same host.
An example of this is having multiple JVM processes that use the same
set of Java EE classes.
When these common classes are loaded and used, new symbols and strings
may be created and added to the JVM\[aq]s internal "symbol" and "string"
! tables.
! At runtime, the symbols or string objects mapped from the archive file
! can be shared across multiple JVM processes, resulting in a reduction of
! overall memory usage.
! In addition, archiving strings also provides added performance benefits
! in both startup time and runtime execution.
.PP
In JDK 10 and later, CONSTANT_String entries in archived classes are
resolved to interned String objects at dump time, and all interned
String objects are archived.
However, even though all CONSTANT_String literals in all archived
*** 5595,5605 ****
Symbol data should be generated by the \f[CB]jcmd\f[R] tool attaching to a
running JVM process.
See \f[B]jcmd\f[R].
.PP
The following is an example of the symbol dumping command in
! \f[CB]jcmd\f[R]:\
.RS
.PP
\f[CB]jcmd\f[R] \f[I]pid\f[R] \f[CB]VM.symboltable\ \-verbose\f[R]
.RE
.RS
--- 5698,5708 ----
Symbol data should be generated by the \f[CB]jcmd\f[R] tool attaching to a
running JVM process.
See \f[B]jcmd\f[R].
.PP
The following is an example of the symbol dumping command in
! \f[CB]jcmd\f[R]:
.RS
.PP
\f[CB]jcmd\f[R] \f[I]pid\f[R] \f[CB]VM.symboltable\ \-verbose\f[R]
.RE
.RS
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