On 13 Feb 2013 07:08, "Maciej Fijalkowski" email@example.com wrote:
We recently encountered a performance issue in stdlib for pypy. It turned out that someone commited a performance "fix" that uses += for strings instead of "".join() that was there before.
Now this hurts pypy (we can mitigate it to some degree though) and possible Jython and IronPython too.
How people feel about generally not having += on long strings in stdlib (since the refcount = 1 thing is a hack)?
What about other performance improvements in stdlib that are problematic for pypy or others?
Personally I would like cleaner code in stdlib vs speeding up CPython.
For the specific case of "Don't rely on the fragile refcounting hack in CPython's string concatenation" I strongly agree. However, as a general principle, I can't agree until speed.python.org is a going concern and we can get a reasonable overview of any resulting performance implications.
Typically that also helps pypy so I'm not unbiased.
Cheers, fijal _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: