The below image depicts that class has 100. The JProfiler main window opens and we navigate to the Live Memory session -> All Objects selection on the left of the window. uncomment following line to fix the memory leakįor (int i = 0 i Run. Throw new RuntimeException("underflow!")
The below classes have been created in Java Project inside IntelliJ IDEA 14.1.2 and built with JDK 1.7.0_79: To profile your application from IntelliJ IDEA, click on the corresponding toolbar button or choose one of the profiling commands in the context menu in the editor or in the Run menu: You should now see a menu entry Run->Profile in IDEA’s main menu. A file selector will then prompt you to locate the installation directory of IntelliJ IDEA.Īfter acknowledging the completion message, you can start IntelliJ IDEA and check whether the installation was successful. If you are performing the installation from JProfiler’s setup wizard, please complete the entire setup first before starting IntelliJ IDEA. Reminder: Please close IntelliJ IDEA while performing the plugin installation. The installation of the IntelliJ IDEA plugin is started by selecting “IntelliJ IDEA ” on the IDE integration tab of JProfiler’s setup wizard miscellaneous options tab of JProfiler’s general settings (use Session->IDE integrations in JProfiler’s main menu as a shortcut) and clicking on
The fourth mode is used when the use of a JProfiler GUI is not desired or technically possible (“Offline mode”). A compromise is to load the profiling agent at startup and tell it later on what the profiling settings should be (“Prepare for profiling”). It is most convenient to simply attach the JProfiler GUI to any running JVM (“Attach mode”), but it is most efficient to load the profiling agent and startup and tell it about the profiling settings immediately (“Profile at startup”). The three GUI modes result from trade-offs between convenience and efficiency. Three of them involve a connection with the JProfiler GUI so you can see and analyze data immediately. There are four different profiling modes in JProfiler. It also helps to see unnecessary eager loading or lazy loading annotations. This is helpful to identify the called JPQL query and on the other side to see wether loading of an entity results in a join-statement or is done in subselects. The same applies to very frequently called expensive java operations.Īnother useful feature of JProfiler when using JPA in an application, is to track JPQL queries and cumulate them with the provider-generated JDBC statements in the view (as long as showing the JPA and JDBC hotspot statements). Beside of caching data which results from this statements, to improve performance another possible solution should be to dissolve such iterations to a simpler flat execution path like one database query or another algorithm. This statements won’t appear in the statistics of long-running statements on database side, but anyway can cause a performance issue when getting called in loop. Imagine some very short running sql-statements as an example. Also there are specialized views directly visualizing the hotspots. So it is possible to find the hotspots in execution, an important basic functionality for profiling your application. Helpful in finding memory leaks is the facility to view the GC-path based on any class.Īpart from memory profiling, with all profiling tools the developer can analyse method calls and the cpu-time needed to perform the operations. The heap viewer comes with the ability to shows references, computing retained sizes and paths to GC roots. In general VisualVM, shipped with the Java SDK, is enough to create such a report. To find memory leaks, a good starting point is to compare two memory snapshots to find the difference after garbage collection is done. In case of common memory issues, all tools provide good and similar solutions. Many performance problems in enterprise or web applications result from memory (garbage collector) or database access issues. Specifically, we are going to make use of the JProfiler which can be invoked from within the IDE without any further need for session configuration. The purpose of this article is to demonstrate a profiler example in IntelliJ Idea IDE.
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