[Python-Dev] New regex module for 3.2?

[Nick Coghlan]

On Thu, Jul 22, 2010 at 9:34 PM, Georg Brandl <g.brandl at gmx.net> wrote:
> So, I thought there wasn't a difference in performance for this use case
> (which is compiling a lot of regexes and matching most of them only a
> few times in comparison).  However, I found that looking at the regex
> caching is very important in this case: re._MAXCACHE is by default set to
> 100, and regex._MAXCACHE to 1024.  When I set re._MAXCACHE to 1024 before
> running the test suite, I get times around 18 (!) seconds for re.

That still fits with the compile/match performance trade-off changes
between re and regex though. It does make it clear this isn't going to
be a win across the board though - things like test suites are going
to have more one-off regex operations than a long-running web server
or a filesystem or database scanning operation.

Cheers,
Nick.

-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia