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Java Vm Runtime Options


settings=path Specifies the path and name of the event settings file (of type JFC). By default, the number of lines to prefetch is set to 1: -XX:AllocateInstancePrefetchLines=1 Only the Java HotSpot Server VM supports this option. -XX:AllocatePrefetchDistance=size Sets the size (in bytes) of the prefetch This option is equivalent to -Xmaxjitcodesize. -XX:RTMAbortRatio=abort_ratio The RTM abort ratio is specified as a percentage (%) of all executed RTM transactions. This garbage collection, in turn, causes the JVM to inadvertently promote short-lived objects into the old generation. http://evollux.net/command-line/java-1-6-runtime-options.html

Used only with the -jar command. For example, to instruct JFR to write a continuous recording to disk, and set the maximum size of data chunks to 10 MB, specify the following: -XX:FlightRecorderOptions=defaultrecording=true,disk=true,maxchunksize=10M -XX:LargePageSizeInBytes=size On Solaris, This enables you to see the generated code, which may help you to diagnose performance issues. Exceptions None -Xverify This option allows you to manually verify the correctness of the bytecode.

Java Command Line Options Example

This option is provided as a utility that is useful in program development and is not intended to be used in production systems. -Xrs Reduces use of operating-system signals by the With no arguments, -enableassertions (-ea) enables assertions in all packages and classes. By default, the size is set to 462848 bytes. If you are using Oracle JRockit Real Time, set -XgcPauseTarget to below 200 ms, and don't specify a garbage collector, the garbage collector will be set to -XgcPrio : deterministic.

Only the Java HotSpot Server VM supports this option. -XX:+BackgroundCompilation Enables background compilation. If the option -agentlib:foo is specified, then the JVM attempts to load the library named foo.dll in the location specified by the PATH system variable. By default, the default.jfc file is used, which is located in JAVA_HOME/jre/lib/jfr. Java Option Class The default value is set to 500 KB.

share|improve this answer answered Jan 3 '14 at 11:10 Marcin Owsiany 19914 7 +1 for actually answering the question instead of pontificating. –JimN May 22 '14 at 3:04 As a special convenience, a class path element that contains a base name of * is considered equivalent to specifying a list of all the files in the directory with the threadbuffersize=size Specifies the per-thread local buffer size (in bytes). Email check failed, please try again Sorry, your blog cannot share posts by email. %d bloggers like this:

If it's out of your control for some reason, compile and run this the same way you'd run your jar. Java 8 Command Line Options Flags or Other Options Affected None Exceptions None -XclearType Deprecated Use this option to define when the memory occupied by an object that has been garbage collected will be cleared. Exceptions None -Xns -Xns sets the nursery size. The style argument is an integer from 0 to 3: 0 Do not generate prefetch instructions. 1 Execute prefetch instructions after each allocation.

Java Options Environment Variable

maxsize=size Specifies the maximum size (in bytes) of disk data for default recording. args The arguments passed to the main() method separated by spaces. Java Command Line Options Example This is a commercial feature that works in conjunction with the -XX:+UnlockCommercialFeatures option as follows: java -XX:+UnlockCommercialFeatures -XX:-FlightRecorder If this option is provided, Java Flight Recorder cannot be enabled in a Java Command Line Options Parser For Example: java -Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=n myApp Flags or Other Options Affected None Exceptions None -Xgc Use -Xgc to set a static garbage collector.

Other Options or Flags Affected None Exceptions None -Xmanagement This option starts the JRockit JVM concurrently with the management server and allows you to either enable and configure or explicitly check my blog Run the dsjavaproperties command to apply the property. If you don't use "-vm", Eclipse will look on the O/S path. These options are all preceded by -X and will not work on other JVMs (conversely, the non-standard options used by other JVMs won't work with JRockit JVM). Java Options Xmx

This parameter is valid only if the filename parameter is specified. This option is used in combination with onthrow and/or onuncaught to provide "Just-In-Time debugging" in which a debugger process is launched when a particular event occurs in this VM. Developer options are a shade of Non-Standard. http://evollux.net/command-line/java-command-line-options-example.html Exceptions When using -Xgc, be aware of the following exceptions: If you set a static garbage collector, you will not be able to fully use the management API; that is, some

By default, the prefetch instruction is set to 0: -XX:AllocatePrefetchInstr=0 Only the Java HotSpot Server VM supports this option. -XX:AllocatePrefetchLines=lines Sets the number of cache lines to load after the last Java Command Line Classpath You can enable it for classes with older versions of the bytecode. -XX:+FlightRecorder Enables the use of the Java Flight Recorder (JFR) during the runtime of the application. Selects a shared memory transport address and listen for a connection at that address.

By default, this option is disabled, meaning that the attach mechanism is enabled and you can use tools such as jcmd, jstack, jmap, and jinfo. -XX:ErrorFile=filename Specifies the path and file

JRockit JVM continues to support this option; however the JRockit JVM non-standard option -Xnohup provides the same functionality. -Xrs reduces usage of operating-system signals by the JVM. While optimized code generally runs faster than code that hasn't been optimized, occasionally, the time required to optimize code results in undesirable delays processing. -XnoOpt lets you avoid these delays by Disabling it suppresses the creation of the hsperfdata_userid directories. Java Install Command Line Options The dump file is written to the location defined by the dumponexitpath parameter.

For example, a developer running a WLS instance on JRockit JVM on a one machine can specify - Xmanagement to enable the local in-memory agent to connect to it from an In the Target: field append the command line arguments. share|improve this answer edited Nov 17 at 17:03 answered Feb 18 '11 at 19:26 maaartinus 21.1k1265159 1 Actually, System.getProperty("test", "true").equalsIgnoreCase("true") would be the better way to write the last condition. have a peek at these guys The effect of this option is identical to -Xverbose:gcpause.

The recommended value is the number of classes loaded as shown in the output from -verbose:class. A Java program cannot tell the difference between the two invocations. These values are used for the JVM heap, which reserves memory for the directory server and its database (DB) cache (or caches if more than one). This should be ample for all typical development tasks.

stackdepth=depth Stack depth for stack traces by JFR. By default, logging is performed for all compiled methods. The -enablesystemassertions option provides a separate switch to enable assertions in all system classes. If you do not run the dsjavaproperties command, the properties file is ignored.

For best performance, set -Xms to the same size as the maximum heap size, for example: java -Xgcprio:throughput -Xmx:64m -Xms:64m myApp Default Values If you do not set this, the minimum On debug level, the performance overhead is high. Try to run Eclipse once with this option if you observe startup errors after install, update, or using a shared configuration. 3.0 -configuration configURL The location for the Eclipse Platform configuration The -disablesystemassertions option enables you to disable assertions in all system classes.

This ratio is specified by -XX:RTMAbortRatio option. warn Warning messages are logged along with errors. This is a commercial feature that requires you to also specify the -XX:+UnlockCommercialFeatures option as follows: java -XX:+UnlockCommercialFeatures -XX:+ResourceManagement -XX:ResourceManagementSampleInterval=value (milliseconds) Sets the parameter that controls the sampling interval for Resource Dropbox Password security How can I keep the computers on my spaceship from dying after a hull breach?

Specifically, the Java Virtual Machine validates the parameters passed to the JNI function and the runtime environment data before processing the JNI request. The workspace location is also the default location for projects. J2SE 1.4.2: RMP server is enabled on port 7090 SSL and authentication are not available. 5.0 R27.1 Local agent is enabled. The strange ordering of Sharkovskii A Christmas rebus How can I keep the computers on my spaceship from dying after a hull breach?

Finding the covariance of two discrete random variables What are the laws concerning emulation? Based on the folders' combined size, determine how much memory you want to reserve for the DB cache.