Re: rebellious pg stats collector (reopened case)

Laszlo Nagy <gandalf(at)shopzeus(dot)com> writes:
> And the stats collector exited! It cannot be by accident. Last time I
> checked, it had the same problem: tried to poll something. It was in an
> inifinte loop, polling something but always got POLERR. Then because I
> started to trace it, it exited with rval=0 or rval=1.

> I do not understand why it exited after I started to trace it? Is this
> some kind of bug?

AFAICS, the only ways to reach the exit(0) in PgstatCollectorMain are
(1) need_exit becomes set (and the only way for that to happen is
to receive a SIGQUIT signal); or (2) PostmasterIsAlive(true) fails,
which implies that getppid() is returning something different than it
used to.

I wonder whether your tracing tool is affecting the result of
getppid(). Most people would consider that a bug in the tracing tool.

regards, tom lane