Looking through the repo, one change of note that doesn't seem to be documented in the README [0] is that this has an optimization to reduce Copy on Writes in f

Looking through the repo, one change of note that doesn't seem to be documented in the README [0] is that this has an optimization to reduce Copy on Writes in forked workers (under the Py_IMMORTAL_INSTANCES preprocessor guard) by not dirtying pages via refcount changes. Here's the BPO issue [1] that tracks the upstreaming attempt. [0] https://github.com/facebookincubator/cinder/blob/9de726349eb95542e59018553b16622933440da3/README.rst https://github.com/facebookincubator/cinder/blob/9de726349eb... [1] https://bugs.python.org/issue40255 https://bugs.python.org/issue40255