objgraph

I am using pandas.DataFrame in a multi-threaded code (actually a custom subclass of DataFrame called Sound ). I have noticed that I have a memory leak, since the memory usage of my program augments gradually over 10mn, to finally reach ~100% of my computer memory and crash. I used objgraph to try tracking this leak, and found out that the count of instances of MyDataFrame is going up all the time while it shouldn't : every thread in its run method creates an instance, makes some calculations, saves the result in a file and exits ... so no references should be kept. Using objgraph I found that

Using objgraph , I found a bunch of objects like this: Will Python's garbage collector deal with cycles like this, or will it leak? A slightly wider view of the loop: Frédéric Hamidi Python's standard reference counting mechanism cannot free cycles, so the structure in your example would leak. The supplemental garbage collection facility , however, is enabled by default and should be able to free that structure, if none of its components are reachable from the outside anymore and they do not have __del__() methods . If they do, the garbage collector will not free them because it cannot