Testing of retryable reads on MMAPv1 was disabled because of hard to diagnose failures (see SERVER-42711). In order to avoid blocking PYTHON-1934, all retryable reads tests were disabled from the MMAPv1 storage engine at the time. These tests should be re-enabled.
SERVER-42711PyMongo's retryable reads spec tests causes server 4.0 to segfault with MMAPv1
SERVER-42922failCommand + closeConnection can dereference a null session pointer
is caused by
PYTHON-1934Raise an actionable error message when retryWrites fails due to using an unsupported storage engine
is depended on by
SERVER-44815Adding arbiter to PSS deployment using mmap causes 4.0.13 server to segfault