>
> Hello,
> I'm trying to install PostgreSQL 7.4.2 on a brand new SunFire 120 with
> 2GB of RAM but when I run initdb -D /usr/local/pgsql/data I get the
> following error:
>
[snip]
> creating template1 database in /usr/local/pgsql/data/base/1... FATAL: could
> not create shared memory segment: Invalid argument
> DETAIL: Failed system call was shmget(key=1, size=1081344, 03600).
> HINT: This error usually means that PostgreSQL's request for a shared
> memory segment exceeded your kernel's SHMMAX parameter.
[snip]
>
> When I run ulimit -a I get
>
[snip]
You're looking at the wrong thing. You need to do:
sysdef |egrep -i 'shm|sem'
>
> There does not seem to be an option in initdb to reduce the shared buffers
> size.
It tries to reduce things as far as it "sanely" can to fit within
what's available. You can hand-tweak initdb to over-ride its
limits, but you'd end-up with a sub-optimal installation.
> Plus, with 2GB of RAM I don't know that I'd want to go below the
> "lowest common denominator" that Postgres defaults to.
Nope. You need to adjust certain values by placing settings in
/etc/system and rebooting. I use:
/etc/system
set shmsys:shminfo_shmmax=0x2000000 (33554432 decimal)
set shmsys:shminfo_shmmin=1
set shmsys:shminfo_shmmni=256
set shmsys:shminfo_shmseg=256
set semsys:seminfo_semmap=256
set semsys:seminfo_semmni=512
set semsys:seminfo_semmns=512
set semsys:seminfo_semmsl=32
I arrived at the above values from Google'ing.
Jim