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. After reading the
documentation I adjusted the semaphore settings in the kernel to allow
Postgresql to start successfully. With this configuration running if I
do a ipcs -u i get the following.
------ Shared Memory Status --------
segments allocated 1
pages allocated 30728
pages resident 30626
pages swapped 0
Swap performance: 0 attempts 0 successes
------ Semaphore Status --------
used arrays = 1880
allocated semaphores = 31928
------ Messages: Status --------
allocated queues = 0
used headers = 0
used space = 0 bytes
I'm questioning the number of semaphores being used. In order for
postgresql to start I had to set the maximum number of semaphores system
wide to 6000000. This seems to be an abnormal amount of semaphores. I'm
curious if this is a bug in the amd64 postgresql port. Is anyone else
using postgresql on an AMD64 machine without similar issues?
TIA
Mark