maps do not shrink after elements removal (delete)

[jiaoji100]

when I use delete map[somekey] in my code, I find that golang will not delete the key, but mark the key as empty instead.

Here are my questions:
when a key was marked as empty, golang’gc will not free the memory? This map may cause memory leak, Is that reasonable?

[patrickmn]

I think this is more about Go's builtins than go-cache. It seems like there's a relevant issue here: golang/go#20135