Clear all lru_cache in Python

Question

I have functions in python that have caches with lru_cache e.g.

 @lru_cache(maxsize=None)
 def my_function():
    ...

While i can individually clear the caches with e.g. my_function.cache_clear() is there any way of clearing the caches of every function at once? [I was thinking that maybe there is a way of returning all function names loaded in memory, and then loop over them clearing the cache from each].

I'm specifically looking to implement as part of a fall-back, for cases where say 90% of the memory on my machine gets used.

Answer 1

maybe there is a way of returning all function names loaded in memory, and then loop over them clearing the cache from each

Yes that is possible as well:

import functools
import gc

gc.collect()
wrappers = [
    a for a in gc.get_objects() 
    if isinstance(a, functools._lru_cache_wrapper)]

for wrapper in wrappers:
    wrapper.cache_clear()

I'm specifically looking to implement as part of a fall-back, for cases where say 90% of the memory on my machine gets used.

This is code you will probably not use under normal circumstances, but can be useful for debugging.

In my particular case I wanted to clear some dangling file handles from matplotlib (in order to focus on my own loose file handles), so it was not possible to use the solution by Alex Hall.