[Python-Dev] The memo of pickle

[Martin v. Loewis]

pickle currently puts tuples into the memo on pickling, but only ever
uses the position field ([0]), never the object itself ([1]).

I understand that the reference to the object is needed to keep it
alive while pickling.

Unfortunately, this means one needs to allocate 36 bytes for the
tuple.

I think this memory consumption could be reduced by saving the objects
in a list, and only saving the position in the memo dictionary. That
would save roughly 32 bytes per memoized object, assuming there is no
malloc overhead.

What do you think?

Regards,
Martin

P.S. It would be even more efficient if there was an identity
dictionary.