reduce gc_collect_harder default to 1 on CPython#14441
Draft
miketheman wants to merge 1 commit intopytest-dev:mainfrom
Draft
reduce gc_collect_harder default to 1 on CPython#14441miketheman wants to merge 1 commit intopytest-dev:mainfrom
miketheman wants to merge 1 commit intopytest-dev:mainfrom
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The 5-iteration default was borrowed from the Trio project, where it was determined empirically to handle PyPy's object resurrection behavior: on PyPy, objects like coroutines can survive GC rounds because executing their __del__ can resurrect them. On CPython, reference counting frees most objects immediately. One GC pass is sufficient to handle reference cycles, as confirmed by all test_unraisableexception tests passing (including the refcycle variants). Use 1 pass on CPython and retain 5 on PyPy. Signed-off-by: Mike Fiedler <miketheman@gmail.com>
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Draft, since I'm not certain this is a good idea. |
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The 5-iteration default was borrowed from the Trio project, where it was determined empirically to handle PyPy's object resurrection behavior: on PyPy, objects like coroutines can survive GC rounds because executing their del can resurrect them.
On CPython, reference counting frees most objects immediately. One GC pass is sufficient to handle reference cycles, as confirmed by all test_unraisableexception tests passing (including the refcycle variants).
Use 1 pass on CPython and retain 5 on PyPy.