Accessing converted C++ class from python is 10-20 times slower

boostorg / python

Boost.org python module

http://boostorg.github.io/python

Boost Software License 1.0

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Accessing converted C++ class from python is 10-20 times slower #356

Open leryss opened 3 years ago

leryss commented 3 years ago

What is boost python actually doing when accessing a C++ class field from python. I could live with the overhead from calling functions but just accessing int/bool fields is 10-20 slower than a native python class.

Tested this by making two identical classes one in native python one in C++ and accessing a single integer field. Access in the C++ class seems to be 10 times slower. Can I do anything to improve this ?

duburcqa commented 2 years ago

I'm wondering too. But I noticed this limitation quite a long time ago (more than 5 years) and therefore when I need efficiency I always wrap the data as numpy scalar, so that I can return a reference from C++ to Python and create a wrapper around the bindings to return the numpy scalar instead of accessing the field of the underlying C++ object. It is tedious and partially defeat the purpose on boost python I did not find any other solution...