013 - 关于GC root: Native Stack | MAT分析

 

Question:

 

I have some third library code that I run and after some time I run into OutOfMemoryError. So I fired up the Eclipse MAT and analyzed the memory. Now it seems the memory can‘t be disposed because there is an object that is a shown as GC root: Native Stack

 

 

Answer:

 

Objects being shown as GC root: Native Stack turned out to be a problem of the Eclipse Debugger. When the application was started without the debugger (i.e. with ‘run‘ instead of ‘debug‘) the problem disappeared. This was also the reason that I couldn‘t find the code where the objects where used in JNI inside my project (cause they weren‘t).

The same problem appears when using IntelliJ Debugger

 

 

简单说：

   通过Eclipse或者IntelliJ  采用debug模式启动程序时，发生内存溢出错误后，由于存在 GC root: Native Stack，导致发生错误的方法中创建的对象无法释放 （正常情况下，发生错误后，方法调用结束，对象会被正常释放的）。

解决方法：采用run运行（非debug模式），就不会存在该问题了013 - 关于GC root: Native Stack  |  MAT分析