Re: Postgresql on an AMD64 machine

Mike Rylander <mrylander@gmail.com> writes:
> On 06 Jun 2005 12:53:40 -0500, Mark Rinaudo <mark@bowmansystems.com> wrote:
>> I'm not sure if this is the appropriate list to post this question to
>> but i'm starting with this one because it is related to the performance
>> of Postgresql server.  I have a Penguin Computing dual AMD 64 bit
>> opteron machine with 8 Gigs of memory.  In my attempt to increase the
>> number of shared_buffers from the default to 65000 i was running into a
>> semget error when trying to start Postgresql.

> Did you perhaps disable spinlocks when compiling PG?

That sure looks like it must be the issue --- in a normal build the
number of semaphores needed does not vary with shared_buffers, but
it will if Postgres is falling back to semaphore-based spinlocks.
Which is a really bad idea from a performance standpoint, so you
want to fix the build.

Which PG version is this exactly, and what configure options did
you use?  What compiler was used?

            regards, tom lane