[New-bugs-announce] [issue2303] isinstance is 4x as slow as in 2.5 because the common case raises

[Jeffrey Yasskin]

New submission from Jeffrey Yasskin <jyasskin at gmail.com>:

r58099 added an exception to the common case of PyObject_IsInstance(),
when the class has no __instancecheck__ attribute. This makes
isinstance(3, int) take 4x as long as in python 2.5.

----------
assignee: gvanrossum
components: Interpreter Core
messages: 63580
nosy: gvanrossum, jyasskin
severity: normal
status: open
title: isinstance is 4x as slow as in 2.5 because the common case raises
type: behavior
versions: Python 2.6

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Tracker <report at bugs.python.org>
<http://bugs.python.org/issue2303>
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