Re: Problem with frequent crashes related to semctl

Adrian Maier <adrian.maier@thalesgroup.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