Subject: Re: Kernel Config - SHMMAXPGS
To: Ian Harding <ianh@tpchd.org>
From: Ian Harding <ianh@tpchd.org>
List: port-i386
Date: 02/04/2004 11:29:02
Thanks for the reply! I have _obviously_ done something wrong in =
compiling the new kernel. Here is the output of ipcs -M
bash-2.05b# ipcs -M
shminfo:
shmmax: 8388608 (max shared memory segment size)
shmmin: 1 (min shared memory segment size)
shmmni: 128 (max number of shared memory identifiers)
shmseg: 128 (max shared memory segments per process)
shmall: 2048 (max amount of shared memory in pages)
On the 1.5.2 machine, the "shmall" entry is the number of pages I have =
configured as SHMMAXPGS.
It's just not that hard to compile a kernel! I thought I followed the =
directions in the FAQ, I must be slipping.
I will start over from scratch.
Thanks!
<<< Patrick Welche <prlw1@newn.cam.ac.uk> 2/ 4 6:16a >>>
On Mon, Feb 02, 2004 at 12:34:50PM -0800, Ian Harding wrote:
> I have compiled a kernel having made the following changes to my=20
> configuration
>=20
> < #options SEMMNI=3D10 # number of semaphore identifiers
> < #options SEMMNS=3D60 # number of semaphores in system
> < #options SEMUME=3D10 # max number of undo entries per =
process
> < #options SEMMNU=3D30 # number of undo structures in system
> ---
> > options SEMMNI=3D256 # number of semaphore identifiers
> > options SEMMNS=3D512 # number of semaphores in system
> > options SEMUME=3D40 # max number of undo entries per =
process
> > options SEMMNU=3D256 # number of undo structures in system
> 80c80
> < #options SHMMAXPGS=3D1024 # 1024 pages is the default
> ---
> > options SHMMAXPGS=3D16192 # 1024 pages is the default
I think you are fine:
Just for reference my configuration says:
options SHMMAXPGS=3D32768 # 2048 pages is the default
# PostgreSQL notes:
#options SHMMAXPGS=3D8192 # (2048) 512 kB + 8192 * buffers + extra
#options SEMMNI=3D64 # (10) >=3D ceil(max_connections / 16)
#options SEMMNS=3D256 # (60) ceil(max_connections / 16) * 17 + extra
(on i386, 1 page =3D 4k)
You have 1000 buffers, 16 connections, so
512 kB + 8k * 1000 buffers =3D 8512kB =3D 2128 pages < 16192 pages as =
configured.
> IpcMemoryCreate: shmget(key=3D5432001, size=3D10035200, 03600) failed:=20=
and size < 16192*4k
So, could it be that your pages are still in use? eg., if you switch off
the postmaster, does
ipcs -a
still show you entries for postgres? (ipcrm lets you clear them)
Cheers,
Patrick
=20