Re: regex cache - Mailing list pgsql-hackers

From Tom Lane
Subject Re: regex cache
Date
Msg-id 8235.1213825854@sss.pgh.pa.us
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In response to Re: regex cache  (Josh Berkus <josh@agliodbs.com>)
Responses Re: regex cache  (Josh Berkus <josh@agliodbs.com>)
List pgsql-hackers
Josh Berkus <josh@agliodbs.com> writes:
>> Having said that, I'm not sure it'd help your problem.  If your query is
>> using more than 32 regexes concurrently, it likely is using $BIGNUM
>> regexes concurrently.  How do we fix that?

> Hmmm.  I think there's a lot of ground between 32 and $BIGNUM.  For example, 
> where I'm hitting a wall is 300 regexes.  Some quick testing on my opteron 
> text machine right now shows that the execution time difference between 20rx 
> and 50rx is around 20x.

Hmm.  Well, I still don't want to tie it to work_mem; how do you feel
about a new GUC to determine the max number of cached REs?
        regards, tom lane


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