Re: PG Seg Faults Performing a Query

Bill Thoen <bthoen(at)gisnet(dot)com> writes:
> I'm a bit out of my depth with using these debugging tools and
> interpreting their results, but I think the problem is due to the output
> being just too big for interactive display.

Well, I can certainly believe it's related to the amount of data
involved, but the exact relationship is far from clear. popen()
doesn't do any actual data-pushing, it just sets up a pipe and forks
a child process --- so even if the child fails immediately after being
forked, that wouldn't lead to the problem seen here. The rarity of
a failure here explains why we hadn't noticed the lack of error checking
long ago.

What I suppose is that you are running into some system-wide resource
constraint. Exactly which one, and whether it's easy to fix, remain to
be seen.

> I tried using strace, but it produced so much telemetry and
> unfortunately I couldn't understand it anyway that I don't think this
> would do me any good.

Sorry, I should have said: the last few dozen lines before the crash are
all that will be interesting.

regards, tom lane