Message11416

I rechecked the problem encountered in an earlier Jython version (2.5.2) which was a memory leak described in this bug report: http://bugs.jython.org/issue2026 . The bug is marked as fixed and I wanted to double check this. Therefore, I used the code snipped contained in the bug report to reconstruct the issue. The original issue seems to be resolved, but I encountered another problem. If I run the aforementioned code for a short period of time, the consumed heap increases quite fast: ~120MB after ~60 seconds. I inspected the heap dump and most the memory is consumed by a ConcurrentHashMap in PySystemState. I took a quick peek at the source and found this:

PySystemState has a static final ConcurrentHashMap named sysClosers [0]. If a new PySystemStateCloser is created, a Key-Value-Pair of a WeakReference to a PySystemState and a reference to the PySystemStateCloser is added to the map [1], but never removed. Even if the WeakReference is finalized, if looks like the value will still remain in the map, since there is no removal code for broken references.