Milter-greylist

Emmanuel Dreyfus wrote:
 > eclark wrote:
 > > > Perhaps it might be worth adding PCRE support to milter-greylist. At least
 > > > then those who link against it would know they were using a reasonably fast
 > > > regex library. 
 > > Whats everyones idea on this? It seems like it would be a really good idea to 
 > > me at the very least.
 > 
 > I don't care as I don't have performances issues :-)
 > Such a feature can get in if someone contribute it, but wait for 3.0 to 
 > be released first.

A quick test on FreeBSD 6 reveals that pcre is about
2.3 times slower than the native regex(3) library.
Maybe that's because of the many bloated features of
perl REs that are not present in POSIX REs.  Therefore
I would recommend against using pcre, at least not
without carefully benchmarking it on different plat-
forms.

Oh by the way, I wasn't able to measure any difference
between "*" and "{,}".  They perform exactly at the
same speed, at least with regex(3) on FreeBSD 6.

(If anything, I would have expected "{,}" to be slower
because it requires either more states in the DFA/NFA,
or additional bookkeeping within the state, compared
to "*".)

Best regards
   Oliver

-- 
Oliver Fromme,  secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing
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