Re: 8.4-vintage problem in postmaster.c

Alvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org> writes:
> Stefan Kaltenbrunner reported a problem in postmaster via IM to me. I
> thought I had nailed down the bug, but after more careful reading of the
> code, turns out I was wrong.

> The reported problem is that postmaster shuts itself down with this
> error message:

> 2010-11-12 10:19:05 CET FATAL: no free slots in PMChildFlags array

Just looking at it, I think that the logic in canAcceptConnections got
broken by somebody in 8.4, and then broken some more in 9.0: in some
cases it will return an "okay to proceed" status without having checked
for TOOMANY children. Was this system possibly in PM_WAIT_BACKUP or
PM_HOT_STANDBY state? What version was actually running?

regards, tom lane