[SOLVED] PhysicsSpace create and destroy will trigger memory LEAK

Yang_Qiu · March 17, 2023, 4:13am

Alike question: https://hub.jmonkeyengine.org/t/memory-leak-using-multiple-parallel-physics-spaces-native-bullet/35743

Example Demo code: GitHub - qiunet/Jme3MemoryLeak: Jme3 Memory Leak demo
ENV: MACOS Big sur JDK 8

Run the example code above, The memory in monitor rise up continuious until process be kill by system!
I do not know is it a bug? Or incorrect use!

sgold · March 17, 2023, 5:28am

            <groupId>org.jmonkeyengine</groupId>
            <artifactId>jme3-bullet-native</artifactId>
            <version>3.3.2-stable</version>

jme3-bullet is no longer maintained. Please switch to jme3-jbullet, or better yet, Minie.

Ali_RS · March 17, 2023, 5:53am

By the way, I am not sure if it is safe to destroy physics space from a different thread than it is created in.

github.com

qiunet/Jme3MemoryLeak/blob/303c7df58cbe8778f7712ac552381a0ae84964df/src/main/java/org/example/ServerMain.java#L34


      
              server.start(JmeContext.Type.Headless);
          
          

          
    AtomicInteger counter = new AtomicInteger();
              int i = 0;
              for (;;) {
                  Room room = new Room(server, i ++);
                  counter.incrementAndGet();
                  service.schedule(() -> {
                      counter.decrementAndGet();
                      room.destroy();
                  }, ThreadLocalRandom.current().nextInt(10, 50), TimeUnit.SECONDS);
                  System.out.println("Create total count: "+i+", Current alive count:" + counter.get());
                  Thread.sleep(ThreadLocalRandom.current().nextInt(200, 900));
              }
          }
          
          
@Override
          public void simpleInitApp() {
              this.setPauseOnLostFocus(false);
              this.setDisplayStatView(false);

maybe you should use the app.enqueue(() -> room.destroy()) to make sure it is destroyed from the JME thread.

or else move the physicsSpace.destroy(); code from the stateDetached() into the cleanup() method of the Room app state because cleanup is always executed from the JME thread.

Yang_Qiu · March 17, 2023, 6:51am

It it work, thanks!

Yang_Qiu · March 17, 2023, 7:00am

Thank you, Maybe it is a cause to leak too!

sgold · March 17, 2023, 7:08am

it work, thanks!

You’re welcome.
And by the way, welcome to the JMonkeyEngine forum!