Re: multiple runs of the same query cause out of memory - WAS [Re: capturing/viewing sort_mem utilization on a per query basis]

Lonni J Friedman <netllama(at)gmail(dot)com> writes:
> We have found that this query can indeed cause terrible things to
> happen to postgresql - it can run several times with response times of
> a few seconds, and then the next time cause postgres to go out of
> control on memory usage. (I've had to reboot my machine twice to get
> control). On a beefier machine with more memory and two CPUs, the
> query worked okay for a few dozen repetitions (with a few in
> parallel), then eventually one instance would cause the postgres
> process to spiral out of control and consume more
> and more memory at the rate of a megabyte every second or so.

> I'm not quite sure where to go from here, but this is definitely
> reproducable now. Help?!

That's a bit hard to believe --- if nothing is changing, the query
should get processed the same way every time.

Can you package up a test case for other people to look at?

regards, tom lane