Subject: Re: increasing share memory
To: Caffeinate The World <mochaexpress@yahoo.com>
From: Giles Lean <giles@nemeton.com.au>
List: netbsd-users
Date: 03/03/2002 19:49:19
<mochaexpress@yahoo.com> wrote:

> i have a need to increase the shared memory for PostgreSQL. how do i do
> that on NetBSD? is it possible to increase. man sysctl says i can't
> increase it via sysctl. my current setting is:
> 
> kern.sysvshm = 1
> 
> what does the 1 represent and what unit is it in?

A boolean reporting the presence or absence of SysV shared memory
support in the kernel perhaps? Kernels built without the SYSVSHM
option don't have SysV shared memory support.

To increase the amount of available SysV shared memory you can build
a new kernel with an increased value for SHMMAXPGS.  I use:

  options 	SHMMAXPGS=32768	# 1024 pages is the default

I don't think this is tunable at runtime, but if it is I'm sure
someone will say so. :-)

Regards,

Giles