[issue2115] __slots__ make attribute setting 10x slower

[Amaury Forgeot d'Arc]

Amaury Forgeot d'Arc added the comment:

This slowdown is due to the new implementation of isinstance in python2.6.

If I comment most of the code of PyObject_IsInstance in
Objects/abstract.c (remove all __instancecheck__ stuff; leave only the
last line), timings are much better, and more similar to 2.5 performance.

----------
nosy: +amaury.forgeotdarc

__________________________________
Tracker <report at bugs.python.org>
<http://bugs.python.org/issue2115>
__________________________________