Re: Uninterruptable regexp_replace in 9.3.1 ?

On 02/21/2014 05:17 PM, Sandro Santilli wrote:
> The following snippet reveals that 9.3.1 has a bug
> in regexp_matches, which uninterruptably keeps CPU
> spinning for minutes:

Huh. So it does. That's interesting.

(You should generally report things to pgsql-bugs@postgresql.org btw,
not -hackers)

Looks like it's busily looping within the regex.c code, never hitting a
CHECK_FOR_INTERRUPTS.

The real question IMO is why it's taking so long. It looks like
cfindloop(...) is being called multiple times, with each call taking a
couple of seconds.

A profile of the run is attached. I don't expect to have a chance to dig
into this right away, as I haven't touched the regexp code before and
would need to spend a bit of time studying it to achieve anything.
Hopefully the test, confirmation, and profile is useful.

--
 Craig Ringer                   http://www.2ndQuadrant.com/
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