## Offline profiling |

| JProfiler's offline profiling capability allows you to run profiling sessions from the command line without the need for starting JProfiler's GUI front end. Offline profiling makes sense if you want to perform profiling runs from a scripted environment (e.g. an ant build file) save snapshots on a regular basis for QA work profile server components on remote machines via slow network connections Performing an offline profiling run for your application is analogous to remote profiling with special library parameters passed to the profiling agent VM parameter `-Xrunjprofiler` for Java <=1.4.2 (JVMPI) or `-agentlib:jprofilerti` for Java >=1.5.0 (JVMTI): offline switch Passing `offline` as a library parameter enables offline profiling. In this case, a connection with JProfiler's GUI is not possible. session ID In order for JProfiler to set the correct profiling settings, a corresponding session has to be configured in JProfiler's GUI front end. The ID of that session has to passed as a library parameter: `id=nnnn`. Your settings in the profiling settings dialog are used for offline profiling. The session ID can be seen in the top right corner of the application settings dialog. config file location (optional) The config file that is read for extracting the session with the specified ID has to be passed via `config={path to config.xml}`. The config file is located in the `.jprofiler4` directory in your user home directory (on Windows, the user home directory is typically `c:\Documents and Settings\$USER`). If you leave out this parameter, JProfiler will try to detect the config file location automatically. A summary of all library parameters is available in the remote session invocation table. If you profile on a machine where JProfiler is not installed, you will need to transfer the contents of the `bin/{your platform}` directory as well as the JAR file `bin/agent.jar` and the config file `{User home directory}/.jprofiler4/config.xml`. Example: A typical invocation for offline profiling with Java >=1.5 (JVMTI) will look like this:
            java "-agentlib:jprofilerti=offline,id=109,config=C:\Documents and Settings\bob\.jprofiler4\config.xml"
            "-Xbootclasspath/a:C:\Program Files\JProfiler\bin\agent.jar"
            -classpath myapp.jar com.mycorp.MyApp
Please study the remote session invocation table to generate the correct invocation for your JVM. Also, please don't forget that the platform-specific native library path has to be modified, just like for remote profiling.

| If you start your application from an ant build file, you can use the ant task to easily profile your application in offline mode.

| If you already have a local session defined, you can generate a start script for offline profiling with the local to offline conversion wizard on the "Convert" tab of the start center or by selecting Session->Conversion wizards->Convert local session to offline from the main menu.

| To control CPU profiling, triggering of heap dumps and saving of snapshots during an offline profiling session, please use JProfiler's profiling API. An example on how to use the offline profiling API is available in the `$JPROFILER_HOME/api/samples/offline` directory.

| If wish to analyze profiling information at run-time, you can use the profiling platform that is part of JProfiler. Please see the javadoc in `$JPROFILER_HOME/api/javadoc` and the sample in `$JPROFILER_HOME/api/samples/platform` for more information.