The PR for this looks good to go: https://github.com/python/cpython/pull/13612
But, I still have no idea how it works for the OP's original test case. So, if you have at least 80 GB of RAM to try it, I added `arena.py` to the BPO report: https://bugs.python.org/issue37029 That adds code to the OP's test case to display the times needed to build the tree and to tear it down (& to display some obmalloc stats). So there's no need for you to think about anything ;-) I'm keen to get feedback on this before merging the PR, because this case is so very much larger than anything I've ever tried that I'm wary that there may be more than one "surprise" lurking here. The PR certainly addresses "an obvious" (with hindsight) problem - but is that the _only_ gross design flaw here? _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com