I was taking a look at dictobject.c and realized that the logic
controlling whether a resizedict will occur in
dict_set_item_by_hash_or_entry disallows for the shrinking of a
dictionary. This is contrary to what the comments directly above say:
(http://hg.python.org/cpython/file/f3032825f637/Obje
True, but your example mechanism of getting a shrink event is purely
based on ma_fill. This is happening because your last loop is
increasing ma_fill to the point where it thinks it needs to resize
because of the load factor and then it calculates the new size based
on ma_used. The comment that I
So I did a bit of benchmarking and attached is the code I used. With
downsizing happening when ma_used * 2 <= ma_filled, or the following
for the condition in question:
if (mp->ma_used <= n_used || (mp->ma_fill*3 < (mp->ma_mask+1)*2 &&
mp->ma_used*2 > mp->ma_fill))
I see marginally faster pe
