why matches($title,'.*?(\.|,)\s*$')) can perform so mu

Hi,

I'm wondering why matches($title,'.*?(\.|,)\s*$')) can perform so much
worse than matches($title,'(\.|,)\s*$'))

I found at least in one file out of thousands that I process the first
one can take a good 30 minutes to complete and the second is quick.

No doubt the .*? causes some problem but what exactly is the problem
that is causes?

Regards

--
Alex Muir
Instructor | Program Organizer - University Technology Student Work
Experience Building
University of the Gambia
http://sites.utg.edu.gm/alex/

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