Grouper Developers Forum

["Michael R. Gettes" <>]

Thanks for the education!!!  Much appreciated.
My concern on regex is withdrawn.

/mrg

On Aug 14, 2008, at 0:32, Chris Hyzer wrote:

> > And, KH, I see you still like the idea of regex and I believe that is
> > overkill as well - why do we need it?  When I consider the many
> > hundreds of thousands of operations we are considering for reasonable
> > sized enterprise deployments - regex processing starts to mount up
> > when you profile the code.  Of course, I should be basing my concern
> > on facts and they are obviously absent, I apologize.  But, from my
> > own experiences, regex processing *can* be expensive when done
> > way too often - and I think this would be one of those cases.
>
> About regex performance, I have never had a problem, (especially  
> since we have to wait for db and ldap io).  This benchmark says that  
> you can do 10k java regexes in 609ms, and the regex looks pretty  
> complex.
>
> http://www.tusker.org/regex/regex_benchmark.html
>
> Remember to keep your regex Pattern objects cached so the  
> expressions aren't recompiled each time.  The book "Java Performance  
> Tuning" agrees, and states that regex is not expensive.  In a  
> benchmark there it says that a regex is only a little slower than a  
> toUpper and compare...  I think regex can be useful, as long as  
> whoever is configuring can figure them out.  :)  Maybe to mitigate  
> the complexity, just put a comment above the config:
>
> #to do a prefix in regex, e.g. starts with 'somePrefix', use  
> something like:      ^somePrefix.*$
>
> Also, we already have regex in the grouper config, and I have been  
> assuming they are fair game...
>
> Chris