Message11234

After more study of this issue I found out that somehow test_json is preparing ground for this deadlock. It sometimes causes guava not to release a certain lock on a cache, which later leads to this deadlock. Especially test_scanstring seems to cause this; I am not yet sure how this can happen.
However it would be helpful if others could confirm the following:
Exclude test_json from regrtests (e.g. insert tests.remove('test_json') into Lib/test/regrtest.py in line 377. There surely is a more proper way to exclude a certain test, feel free to use that one!)
Then, test_logging should not deadlock any more.