-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Antoine Pitrou wrote: > On Wed, 7 Jul 2010 19:44:31 +0200 > Eli Bendersky <eli...@gmail.com> wrote: >> For what it's worth, my benchmarking showed that modifying the >> heuristic to only kick in when there are more than 100 kinds of >> elements (Terry's option A) didn't affect the runtime of matching >> whatsoever, even when the heuristic *does* kick in. All it adds, >> really, is the overhead of a single 'if' statement. So it wouldn't be >> right to assume that somehow modifying the heuristic or allowing to >> turn it off will negatively affect performance in the special case Tim >> originally optimized for. > > Just because it doesn't affect performance in your tests doesn't mean it > won't do so in the general case. Consider a case where Tim's junk > optimization kicked in and helped improve performance a lot, but where > there are still less than 100 alphabet symbols. The new heuristic will > ruin this use case.
That would describe pretty much every C program ever written, for instance, and nearly as high a percentage of all Python modules / scripts ever written: the 'string.printable' set, less formfeed and vertical tab, is 98 characters long. > That's why I'm advocating a dedicated flag instead. +1. Tres. - -- =================================================================== Tres Seaver +1 540-429-0999 tsea...@palladion.com Palladion Software "Excellence by Design" http://palladion.com -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAkw032wACgkQ+gerLs4ltQ5xigCfVLhTzFX733cZAO2Jv6JZQm0i HoIAmQEnTyxa2oLAuE22M7FZHUS00xDu =WYt2 -----END PGP SIGNATURE----- _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com