Java loads dll, causing Java Process Memory leakage

By zhaoch

During the performance test of the network monitoring system, memory leakage has occurred, which has been plagued for a long time. Now it is a solution, but the root cause is still unclear. Let's discuss it with you, see if it can be solved perfectly ~

This strange problem is caused by memory leakage of Java processes, rather than the normal JVM Memory leakage. The problem cannot be seen by tools such as Jprofile.

The test code is as follows:

1 System. loadLibrary ("test1 ");
2
3 int threadPoolSize = 400;
4 ExecutorService service = Executors. newFixedThreadPool (threadPoolSize );
5
6 for (int I = 0; I <400; I ++ ){
7 service. submit (new Runnable (){
8 public void run (){
9 while (true ){
10 try {
11 Thread t = new Thread ();
12 t. start ();
13 Thread. sleep (100 );
14} catch (Exception e ){
15 e. printStackTrace ();
16}
17}
18}
19 });
20}

Note: The job of this code segment is to load a dll and start the thread continuously (the thread stops directly without doing anything ).
Note: The thread pool is only used to accelerate the recurrence of the problem and is useless.

Symptom:
1. If the dll is not loaded, only the thread is continuously started. The memory of the Java Process is normal and will not keep increasing.
2. If the dll test1 in the attachment is loaded, the memory of the Java Process will keep increasing.
3. If you load the test2 dll in the attachment (you need to install the C ++ runtime environment vcredist_x86), the Java Process Memory is normal and will not continue to grow.

Dll description:
The dll project source code is included in the attachment. The difference between test1 and test2 lies only in the compilation options, such as the attachment: test1 selects "use standard Windows library" or "use MFC in static library", test2 selects "use MFC in shared DLL"
This dll project uses jni and introduces the mfc header file [# include <afxwin. h>]. If the mfc header file is not introduced, it will not cause memory leakage.

The root cause of this problem is unclear. I suspect it is a jdk bug (it is useless to use the latest jdk 1.6.0.23). Do you have any idea? Welcome to the discussion ~