On 18-Nov-06, at 11:30 AM, Tom Lane wrote:
Dave Cramer <pg@xxxxxxxxxxxxx> writes:
On 16-Nov-06, at 7:03 PM, Brian Wipf wrote:
Has anyone else noticed this limitation on OS X? Any ideas on how I
might get shared_buffers higher than 284263?
My guess is something else has taken shared memory ahead of you. OS X
seems to be somewhat strange in how it deals with shared memory. Try
allocating more to shmmax ?
Look in "ipcs -m -a" output to check this theory. (I am glad to see
that ipcs and ipcrm are finally there in recent OS X releases ---
awhile
back they were not, leaving people to fly entirely blind while dealing
with issues like this :-()
ipcs -m -a
Shared Memory:
T ID KEY MODE OWNER GROUP CREATOR CGROUP
NATTCH SEGSZ CPID LPID ATIME DTIME CTIME
m 196607 5432001 --rw------- postgres postgres postgres
postgres 8 -2100436992 223 223 23:00:07 2:49:44 23:00:07
(I also bumped shmmax and shmall to 6GB with the same shared_buffers
limit.)
It certainly is unfortunate if Guido's right and this is an upper
limit for OS X. The performance benefit of having high shared_buffers
on our mostly read database is remarkable.
