On 2017-08-01 01:31, t...@tomforb.es wrote: > As part of the Python 3 cleanup in Django there are a fair few uses of > @functools.lru_cache on functions that take no arguments. A lru_cache isn't > strictly needed here, but it's convenient to just cache the result. Some > examples are here: https://github.com/django/django/pull/8825/files > > I did some profiling and I found that using `@lru_cache(maxsize=None)` on > such functions is twice as fast as a standard `@lru_cache()`, apparently > because with a `maxsize` the lru_cache code requires a lock acquisition and a > fair bit more state to track. > > Am I right in thinking that using `maxsize=None` is best for functions that > accept no arguments? Should we even be using a `lru_cache` in such > situations, or write our own simple cache decorator instead?
There is a more elegant and faster approach if you use a non-data descriptor instead of a property or a lru_cache. If you use a non-data descriptor property, you can even get rid of subsequent function calls. I dumped some example code in a gist, https://gist.github.com/tiran/da7d4c43d493c5aa7d7abc4d8a0678a6 Christian -- https://mail.python.org/mailman/listinfo/python-list
