7.1 Options and properties used in Java VM : Hitachi Application Server V10 Definition Reference Guide (For UNIX Systems)

Notes

The default values of the Java VM options and properties described here might differ from the default values of the servers.
For details on the default values of the servers, see the description Changing Java VM options by using the create-jvm-options subcommand in the User's Guide.

Java VM options used for list displays

Option	Overview	Details
7.2.1 -XX:+Hitachi	Displaying a list of extended Java VM options	Displays a list of extended Java VM options.

Java VM options used for the extended thread dump functionality

Option	Overview	Details
7.3.1 -XX:[+\|-]HitachiThreadDump	Outputting extended thread dump information	Specifies whether to output extended thread dump information.
7.3.2 -XX:[+\|-]HitachiThreadDumpToStdout	Outputting extended thread dumps to the standard output	Specifies whether to output extended thread dumps to the standard output.
7.3.3 -XX:[+\|-]HitachiThreadDumpWithBlockCount	Outputting the following information as the thread information of extended thread dumps: the number of times that thread processing was blocked and the number of times the thread was in the wait status	Specifies whether to output the following information as the thread information of extended thread dumps: the number of times that thread processing was blocked and the number of times the thread was in the wait status.
7.3.4 -XX:[+\|-]HitachiThreadDumpWithCpuTime	Outputting the following information as the thread information of extended thread dumps: user CPU time and kernel CPU time	Specifies whether to output the following information as the thread information of extended thread dumps: user CPU time and kernel CPU time.
7.3.5 -XX:[+\|-]HitachiThreadDumpWithHashCode	Outputting hash codes as the thread information of extended thread dumps	Specifies whether to output hash codes as the thread information of extended thread dumps.

Java VM options used for Java VM log files

Option	Overview	Details
7.4.1 -XX:HitachiJavaLog	Specifying the prefix and the output-destination directory of Java VM log files	Specifies the prefix and the output-destination directory of Java VM log files.
7.4.2 -XX:HitachiJavaLogFileSize	Specifying the maximum size for each Java VM log file	Specifies the maximum size for a single log file. This specification prevents the size of log files from increasing. If the size of a file reaches the maximum size, no logs are output to the file.
7.4.3 -XX:[+\|-]HitachiJavaLogNoMoreOutput	Specifying how to output log information if an input or output error occurs during log file creation	Specifies how to output log information if an input or output error occurs during log file creation. Note that Java VM continues processing regardless of the specified value. This option applies to Java VM log files and the log files for the explicit memory management functionality.
7.4.4 -XX:HitachiJavaLogNumberOfFile	Specifying the maximum number of Java VM log files that are to be created	Specifies the maximum number of Java VM log files that are to be created. This specification prevents the number of created files from increasing.
7.4.5 -XX:[+\|-]JavaLogAsynchronous	Enabling or disabling the asynchronous output functionality for log files	Specifies whether to enable or disable the asynchronous output functionality for log files.
7.4.6 -XX:[+\|-]JavaLogHeaderOutput	Outputting the header information when a Java VM log file is opened	Specifies whether to output the header information when a Java VM log file is opened. The header information contains the following information: the Java VM version in the 1st line, and the startup command line information in the 2nd line. You must take into account the size of the output header information when specifying the maximum file size for the `-XX:HitachiJavaLogFileSize` option. This option applies to Java VM log files and the log files for the explicit memory management functionality.
7.4.7 -XX:JavaLogRotationTime	Specifying the rotation time of the Java VM log file	If the rotation type of the Java VM log file is the shift type, specify the time when the storage destination file is to be switched for this option. This option applies to Java VM log files and the log files for the explicit memory management functionality. The Java VM log file will be switched at the time specified in this option.
7.4.8 -XX:JavaLogRotationType	Specifying the rotation type of the Java VM log file	Specifies the rotation type of the Java VM log file. This option applies to Java VM log files and the log files for the explicit memory management functionality.

Java VM option used for the detailed time output

Option	Overview	Details
7.5.1 -XX:[+\|-]HitachiOutputMilliTime	Outputting the time (accurate to the millisecond) to the Java VM log file	Specifies whether to output the time accurate to the millisecond. This option applies to Java VM log files and the log files for the explicit memory management functionality.

Java VM options used for the extended verbosegc functionality

Option	Overview	Details
7.6.1 -XX:[+\|-]HitachiCommaVerboseGC	Outputting the extended verbosegc information in CSV format	Specifies whether to output the extended verbosegc information in CSV format.
7.6.2 -XX:[+\|-]HitachiVerboseGC	Outputting the extended verbosegc information to the Java VM log file when a GC occurs	Specifies whether to output the extended verbosegc information when a GC occurs.
7.6.3 -XX:[+\|-]HitachiVerboseGCCpuTime	Outputting the user CPU time and the kernel CPU time as the extended verbosegc information	Specifies whether to output the CPU usage time as the extended verbosegc information.
7.6.4 -XX:HitachiVerboseGCIntervalTime	Specifying the interval (in seconds) for outputting the extended verbosegc information	Specifies the interval (in seconds) for outputting the extended verbosegc information.
7.6.5 -XX:[+\|-]HitachiVerboseGCPrintCause	Outputting details on the causes of GCs	Specifies whether to output details on the causes of GCs.
7.6.6 -XX:[+\|-]HitachiVerboseGCPrintDate	Outputting the date and time when a GC started to the extended verbosegc information	Specifies whether to output the date and time when a GC started to the extended verbosegc information.
7.6.7 -XX:[+\|-]HitachiVerboseGCPrintDeleteOnExit	Outputting the following information to the Java VM log file: the cumulative heap size allocated by Java VM when java.io.File.deleteOnExit() was called, and the number of times the method was called	Specifies whether to output the following information to the Java VM log file: the cumulative heap size allocated by Java VM when java.io.File.deleteOnExit() was called, and the number of times the method was called.
7.6.8 -XX:[+\|-]HitachiVerboseGCPrintJVMInternalMemory	Outputting the heap information that is internally managed by Java VM, to the Java VM log file	Specifies whether to output the heap information that is internally managed by Java VM, to the Java VM log file.
7.6.9 -XX:[+\|-]HitachiVerboseGCPrintTenuringDistribution	Outputting the age distribution for the Survivor area to the Java VM log file	Specifies whether to output the age distribution for the Survivor area to the Java VM log file when `-XX:+PrintTenuringDistribution` is specified.
7.6.10 -XX:[+\|-]HitachiVerboseGCPrintThreadCount	Outputting the number of Java threads to the Java VM log file	Specifies whether to output the number of Java threads to the Java VM log file. This information can be used to monitor the number of Java threads.

Java VM options used for the functionality that outputs the code cache area information

Option	Overview	Details
7.7.1 -XX:CodeCacheInfoPrintRatio	Specifying the usage threshold rate of the code cache area	Specifies the usage rate of the code cache area. This is the rate at which a message is output to indicate that usage has reached the threshold value.
7.7.2 -XX:[+\|-]PrintCodeCacheFullMessage	Outputting a message to the Java VM log file when the code cache area becomes insufficient during JIT compilation of a Java method	Specifies whether to output a message to the Java VM log file when the code cache area becomes insufficient during JIT compilation of a Java method.
7.7.3 -XX:[+\|-]PrintCodeCacheInfo	Specifying whether to output the following information to the Java VM log file: the usage rate of the code cache area and the message informing the user that usage has reached the threshold value	Specifies whether to output the usage rate of the code cache area. In addition, this option specifies whether to output the message informing the user that usage has reached the threshold value, to the Java VM log file.

Java VM options used for the extended functionality when an OutOfMemoryError occurs

Option	Overview	Details
7.8.1 -XX:[+\|-]HitachiOutOfMemoryAbort	Enabling or disabling the functionality that forcibly terminates processing when an OutOfMemoryError occurs	If an OutOfMemoryError occurs, a message is output to the standard output and processing is forcibly terminated.
7.8.2 -XX:[+\|-]HitachiOutOfMemoryAbortThreadDump	Outputting thread dumps when an OutOfMemoryError occurs	Thread dumps are output when an OutOfMemoryError occurs. When the C heap in the J2SE class library is insufficient, thread dumps are not output, to prevent the recurrence of C heap insufficiency due to the output of thread dumps.
7.8.3 -XX:[+\|-]HitachiOutOfMemoryAbortThreadDumpWithJHeapProf	Outputting class-wise statistics to the thread dump log file that is output when an OutOfMemoryError occurs	Specify whether to output class-wise statistics to the output thread dump log file that is output when `-XX:+HitachiOutOfMemoryAbortThreadDump` is specified. If G1GC is used, this functionality is disabled. If the option that enables this functionality is specified when G1GC is being used, the specification is not applied, and this functionality is disabled.
7.8.4 -XX:[+\|-]HitachiOutOfMemoryCause	Outputting the cause type when an OutOfMemoryError occurs	Specifies whether to output the cause type when an OutOfMemoryError occurs.
7.8.5 -XX:[+\|-]HitachiOutOfMemorySize	Outputting the memory size requested when an OutOfMemoryError occurs	Outputs the memory size requested when an OutOfMemoryError occurs.
7.8.6 -XX:[+\|-]HitachiOutOfMemoryStackTrace	Outputting the exception information and the stack trace to the Java VM log file when an OutOfMemoryError occurs	Specifies whether to output the exception information and the stack trace to the Java VM log file when an OutOfMemoryError occurs.
7.8.7 -XX:HitachiOutOfMemoryStackTraceLineSize	Specifying the number of characters (in bytes) per line of the stack trace that is output when an OutOfMemoryError occurs	Specifies the number of characters (in bytes) per line of the stack trace that is output when an OutOfMemoryError occurs.

Java VM options used for the class library trace functionality

Option	Overview	Details
7.9.1 -XX:[+\|-]HitachiJavaClassLibTrace	Outputting the stack trace for the class library	Outputs the stack trace for the API to the Java VM log file when a method that affects the entire system is used.
7.9.2 -XX:HitachiJavaClassLibTraceLineSize	Specifying the number of characters (in bytes) per line of the stack trace for the class library	Specifies the number of characters (in bytes) per line of the stack trace for the class library that is output when the `-XX:+HitachiJavaClassLibTrace` option is specified.

Java VM options used for the functionality that outputs the local variable information

Option	Overview	Details
7.10.1 -XX:HitachiCallToString	Outputting the character strings of the String objects that were obtained via a local variable object	Outputs the character strings of the String objects that were obtained via a local variable object in a class corresponding to `applicable_range`, as strings that represent variable values.
7.10.2 -XX:[+\|-]HitachiLocalsInStackTrace	Adding the local variable information of each method to the stack traces generated when thread dumps are output, and outputting the stack traces	Adds the local variable information of each method to the stack traces that are generated when thread dumps are output, and then outputs the stack traces.
7.10.3 -XX:[+\|-]HitachiLocalsInThrowable	Outputting the local variable information of the methods in the stack traces	Collects the local variable information of the methods in the stack traces when the java.lang.Throwable.fillInStackTrace method is executed.
7.10.4 -XX:[+\|-]HitachiLocalsSimpleFormat	Changing the output format of local variable information to the simple output format, where one variable is output per line	Changes the output format of the local variable information to the simple output format, where one variable is output per line.
7.10.5 -XX:[+\|-]HitachiTrueTypeInLocals	Outputting actual object type names to the local variable information	Outputs the name of the object type that is set for a class or an array-type local variable when collecting local variable information.

Java VM options used for releasing system resources

Option	Overview	Details
7.11.1 -XX:[+\|-]HitachiFullCore	Creating the `core` file without considering the user limit when a failure occurs	Specifies whether to change the setting of the system resource `RLIMIT_CORE`.

Java VM options used for the explicit memory management functionality

Java VM options used for specifying the maximum values for resources

Option	Overview	Details
7.13.1 -XX:HitachiJITCompileMaxMemorySize	Specifying the maximum memory size of the C heap to be allocated during JIT compilation	Specifies the maximum memory size of the C heap to be allocated during JIT compilation.
7.13.2 -XX:HitachiThreadLimit	Specifying the maximum number of threads	Specifies the maximum number of threads.

Java VM options used for the JIT compiler continuation functionality

Option	Overview	Details
7.14.1 -XX:[+\|-]JITCompilerContinuation	Enabling or disabling the JIT compiler continuation functionality	Specifies whether to enable or disable the JIT compiler continuation functionality.

Java VM options used to execute Java application programs

Option	Overview	Details
7.15.1 -Xhras	Executing Java application programs	If you execute the `java` command or the `javaw` command with this option specified, you will be able to execute Java application programs.

Java VM options used for the functionality for the compressed object pointer

Option	Overview	Details
7.16.1 -XX:[+\|-]UseCompressedOops	Enabling or disabling the compressed object pointer functionality	Specifies whether to enable or disable the compressed object pointer functionality.

Java VM properties used for the finalize-retention-cancellation functionality

Property	Overview	Details
7.17.1 JP.co.Hitachi.soft.jvm.autofinalizer	Enabling or disabling the finalize-retention-cancellation functionality	Specifies whether to enable or disable the finalize-retention-cancellation functionality.

Java VM properties used for performance-based trace analysis

Property	Overview	Details
7.18.1 jvm.userprf.Enable	Enabling or disabling performance-based trace analysis	Specifies whether to enable or disable performance-based trace analysis.
7.18.2 jvm.userprf.ExtendedSetting	Specifying the specification format for the performance-based trace analysis configuration file	Specifies whether to enable each of the following specification formats for the performance-based trace analysis configuration file.
7.18.3 jvm.userprf.File	Specifying the file path for the performance-based trace analysis configuration file	Specifies the file path for the performance-based trace analysis configuration file.
7.18.4 jvm.userprf.Limit	Specifying the maximum number of target methods of the performance-based trace analysis	Specifies the maximum number of target methods of the performance-based trace analysis.
7.18.5 jvm.userprf.LineNumber	Outputting to the trace information, the line number of the last executed statement of the method	Specifies whether to output to the trace information, the line number of the last executed statement of the method when the method ends normally.
7.18.6 jvm.userprf.LogLevel	Specifying the trace output level for performance-based trace analysis	Specifies the output level for the names of traced methods. The names are output in the specified level to the optional information (`OPT`) of the performance-based trace analysis information.
7.18.7 jvm.userprf.ThrowableName	Outputting the names of exception or error classes to the trace information	Specifies whether to output the names of exception or error classes to the operation information (`OPR`) of the trace information when a method ends abnormally.
7.18.8 jvm.userprf.ThrowableNameEditMethod	Specifying how the name of an exception or error class is edited if the name exceeds 32 characters	Specifies how the name of an exception or error class is to be modified if the name exceeds 32 characters. If the name of an exception or error class is 32 characters or less, all characters are output to the trace information regardless of the specification in this property.
7.18.9 jvm.userprf.Trace	Outputting logs when the class file specified in the performance-based trace analysis configuration file is successfully overwritten	Specifies whether to output logs when the class file specified in the performance-based trace analysis configuration file is successfully overwritten.

Java HotSpot VM options used for Application Server

Option	Overview	Details
7.19.1 -agentlib:hndlwrap2	Continuing Java VM execution when a user logs off from Windows	Specifies whether to continue Java VM execution when a user logs off from Windows in an environment that includes JDK version 6 or later.
7.19.2 -agentlib:libname	Loading the native agent library	Loads the native agent library `libname`.
7.19.3 -XX:CompressedClassSpaceSize	Specifying the maximum size of the Compressed Class Space	Specifies the maximum size of the Compressed Class Space.
7.19.4 -XX:ConcGCThreads	Specifying the number of threads that can execute concurrent marking in parallel	Specifies the number of threads that can execute processing for Concurrent Marking in parallel when G1GC is enabled.
7.19.5 -XX:MaxGCPauseMillis	Specifying the target amount of time for which applications are stopped by GC for G1GC	Specifies the target amount of time (in milliseconds) for which applications are stopped by GC for G1GC.
7.19.6 -XX:MaxMetaspaceSize	Specifying the maximum value of the Metaspace area	Specifies the maximum value of the Metaspace area.
7.19.7 -XX:MaxTenuringThreshold	Specifying the threshold value for the number of times Java objects are replaced in the From space and in the To space when CopyGC is executed	Specifies the threshold for the number of times Java objects are replaced in the From space and in the To space when CopyGC is executed. After the specified threshold is exceeded, the Java objects to be replaced are moved to the Tenured area.
7.19.8 -XX:MetaspaceSize	Specifying the standard value for the full GC that originated in the Metaspace area	Specifies the standard value for the full GC that originated in the Metaspace area.
7.19.9 -XX:NewRatio	Specifying the ratio of the Tenured area to the New area	Specifies the ratio of the Tenured area to the New area.
7.19.10 -XX:ParallelGCThreads	Specifying the number of threads that can execute G1GC in parallel	Specifies the number of threads that can execute G1GC in parallel.
7.19.11 -XX:ReservedCodeCacheSize	Specifying the maximum size of the code cache area	Specifies the maximum size of the code cache area.
7.19.12 -XX:SurvivorRatio	Specifying the ratio of the Eden area to each of the following spaces in the Survivor area: the From space and the To space	Specifies the ratio of the New::Eden area to each of the following spaces in the New::Survivor area: the From space and the To space.
7.19.13 -XX:TargetSurvivorRatio	Specifying the target proportion of the Java objects in the Survivor area after GC is executed	Specifies the target proportion (0% to 100%) of the New::Survivor area that is to be made up of Java objects after GC is executed.
7.19.14 -XX:[+\|-]UseG1GC	Executing G1GC	Specifies whether to execute G1GC. This option cannot be specified at the same time as the options (`UseSerialGC` and `HitachiUseExplicitMemory`).
7.19.15 -XX:[+\|-]UseSerialGC	Executing SerialGC	Specifies whether to execute SerialGC.
7.19.16 -verbose:information-type	Outputting the information specified in `information_type`	Outputs the information specified in `information_type`.
7.19.17 -Xloggc:file	Outputting logs to `file` whenever a GC event occurs	Similar to `-verbose:gc`, a report is sent whenever a GC event occurs. In addition, data about the event is recorded in `file`. In addition to the information reported when `-verbose:gc` is specified, the amount of time (in seconds) that has elapsed from the first GC event is included at the beginning of each event report.
7.19.18 -Xms	Specifying the initial size of the JavaHeap	Specifies the initial size of the JavaHeap.
7.19.19 -Xmx	Specifying the maximum size of the JavaHeap	Specifies the maximum size of the JavaHeap.
7.19.20 -Xprof	Generating the profile for a running program, and outputting the profiling data to the standard output	If you specify this option, the profile for a running program is generated, and the profiling data is output to the standard output. This option is provided as a program development utility. This option is not intended for use in a system that is running in the production environment.
7.19.21 -Xss	Specifying the maximum area size per stack	Specifies the maximum area size per stack.

Environment variables used in Java VM

Environment variables	Overview	Details
7.20.1 JAVA_HRAS	An environment variable that enables the `java` command to be executed	If you execute the `java` command with this option specified, you will be able to execute Java application programs that do not link with Application Server.
7.20.2 JAVACOREDIR	Specifying the directory where thread dump files are output	Specifies the directory where thread dump files are output in the C shell.
7.20.3 JAVAW_HRAS	An environment variable that enables the `javaw` command to be executed	If you execute the `javaw` command with this option specified, you will be able to execute Java application programs that do not link with Application Server.

Option	Overview	Details
7.12.1 -XX:ExplicitMemoryAutoReclaimTargetBlockRatio	Specifying the upper limit on the release ratio that is set during the automatic release processing of the explicit memory management functionality	Specify the maximum release rate that can be set in the automatic release processing of the explicit memory management functionality. The release rate is the ratio of the amount of the heap area that is actually released by automatic release processing, to the amount selected during the automatic release processing.
7.12.2 -XX:ExplicitMemoryExcludeClassListFile	Specifying the file path for the explicit memory management functionality exclusion configuration file	Specifies the file path for the explicit memory management functionality exclusion configuration file that is used by the functionality that excludes classes from the explicit memory management functionality. The explicit memory management functionality is not applied to the classes specified in this file.
7.12.3 -XX:ExplicitMemoryFullGCPolicy	Controlling (based on reference relationships) the movement of objects from the JavaHeap to Explicit memory blocks when full GC occurs	Specifies whether to control (based on reference relationships) the movement of objects from the JavaHeap to Explicit memory blocks when full GC occurs. This option enables the objects that were moved to the Explicit heap when full GC occurred, to be moved to the Tenured area.
7.12.4 -XX:ExplicitMemoryNotExcludeClassListFile	Specifying the file path for the configuration file that disables exclusions from the explicit memory management functionality	Specifies the file path for the configuration file that disables exclusions from the explicit memory management functionality. This file is used by the functionality that excludes classes from the explicit memory management functionality. The functionality that excludes classes from the explicit memory management functionality is not applied to the classes specified in this file, even if those classes are also specified in the explicit memory management functionality exclusion configuration file.
7.12.5 -XX:[+\|-]ExplicitMemoryUseExcludeClass	Enabling or disabling the functionality that excludes classes from the explicit memory management functionality	Specifies whether to enable or disable the functionality that excludes classes from the explicit memory management functionality.
7.12.6 -XX:[+\|-]HitachiAutoExplicitMemory	Enabling or disabling the functionality for automatically placing Explicit memory blocks	Specifies whether to enable or disable the functionality for automatically placing Explicit memory blocks.
7.12.7 -XX:HitachiAutoExplicitMemoryFile	Specifying the file path for the automatic placement configuration file used by the functionality for automatically placing Explicit memory blocks	Specifies the file path for the automatic placement configuration file used by the functionality for automatically placing Explicit memory blocks.
7.12.8 -XX:HitachiExplicitHeapMaxSize	Specifying the maximum size of the entire Explicit heap	Specifies the maximum size of the entire Explicit heap.
7.12.9 -XX:[+\|-]HitachiExplicitMemoryAutoReclaim	Enabling or disabling the automatic release of the explicit memory management functionality	Specifies whether to use the automatic release functionality of the explicit memory management functionality.
7.12.10 -XX:[+\|-]HitachiExplicitMemoryAutoRefReclaim	Enabling or disabling the functionality that saves the amount of memory in the Explicit heap that is used for HTTP sessions	Specifies whether to enable or disable the functionality that saves the amount of memory in the Explicit heap that is used for HTTP sessions.
7.12.11 -XX:[+\|-]HitachiExplicitMemoryCompatibleToV8	Specifying whether to allocate Explicit memory blocks by using the same method as 08-00	Specifies whether to allocate Explicit memory blocks by using the same method as 08-00. Enable this option if the applications that were used in 08-00 are to be used in 08-50, instead of the new functionality implemented in 08-50 and later.
7.12.12 -XX:HitachiExplicitMemoryJavaLog	Specifying the prefix and output-destination directory of the log file for the explicit memory management functionality	Specifies the prefix and output-destination directory for the log files of the explicit memory management functionality.
7.12.13 -XX:HitachiExplicitMemoryJavaLogFileSize	Specifying the maximum size (in bytes) per log file of the explicit memory management functionality	Specifies the maximum size (in bytes) per file.
7.12.14 -XX:HitachiExplicitMemoryJavaLogNumberOfFile	Specifying the maximum number of log files that are to be created by the explicit memory management functionality	Specifies the maximum number of Java VM log files that are to be created. This specification prevents the number of created files from increasing.
7.12.15 -XX:HitachiExplicitMemoryLogLevel	Specifying the event log level for the explicit memory management functionality	Specifies the event log level for the explicit memory management functionality.
7.12.16 -XX:[+\|-]HitachiExplicitMemoryMoveToTenuredFirst	Changing the location where objects are moved during the release of Explicit memory blocks, to the Tenured area	Specifies the location where objects are moved during the release of Explicit memory blocks.
7.12.17 -XX:[+\|-]HitachiUseExplicitMemory	Enabling or disabling the explicit memory management functionality	Specifies whether to enable or disable the explicit memory management functionality.