Re: Problem with frequent crashes related to semctl

Adrian Maier <adrian(dot)maier(at)thalesgroup(dot)com> writes:
> I am running PostgreSQL 8.3.5 on a linux machine (Ubuntu 10.04).
> Sometimes it happens that connecting to the database fails with error :

> FATAL: semctl(360458, 3, SETVAL, 0) failed: Invalid argument (PGError)

> If i restart postgres the problem gets "fixed". It doesn't matter how do i
> connect to the database : i saw this happening from psql, from jdbc, and
> from ruby.

The most likely theory is that something deleted Postgres' semaphores
out from under it. You could check this by noting the output of "ipcs -s"
while the database is running normally, and then comparing to the output
after it starts to fail.

If that does seem to be what's happening, look around for root-executed
scripts doing "ipcrm" calls.

regards, tom lane