"Markus Wollny" <Markus.Wollny@computec.de> writes:
> So: Is it bad RAM? How can I make sure? What else could it be?
Have you tried running memtest86? I've never used that myself but
some folks on the list say it works well.
> Here's a small excerpt from the logfile:
> 2002-08-06 17:36:23 [17296] DEBUG: _mdfd_blind_getseg: couldn't open
> /var/lib/pgsql/data/base/base/16596/16671: Cannot allocate memory
Is it possible that you are running with inadequate swap space, a small
data segment limit (ulimit -d), or something else that would make the
kernel refuse to give memory to a backend process?
> 2002-08-06 17:40:53 [16530] DEBUG: connection startup failed (fork
> failure): Cannot allocate memory
> 2002-08-06 17:52:50 [16530] DEBUG: connection startup failed (fork
> failure): Cannot allocate memory
Still looks like inadequate memory --- but now I'm thinking that it's a
system-wide condition, ie, you just plain haven't got enough RAM for the
number of processes you're trying to start.
> 2002-08-06 17:52:54 [16530] DEBUG: server process (pid 18237) was
> terminated by signal 9
Postgres never issues any kill -9 on itself, but I've heard that the
Linux kernel may start killing processes when it's desperately low on
memory.
Other than the signal 9, everything I see in this trace is either a
cannot-allocate-memory failure or followup effects from one. How many
backends are you trying to start up, anyway? Might you have a runaway
client that keeps opening new backend connections?
regards, tom lane
