To: Mark Kirkwood <markir@coretech.co.nz>
Cc: pgsql-docs@postgresql.org
Subject: Re: Instructions for Linux ipc config 
In-reply-to: <4202AE60.6000706@coretech.co.nz> 
References: <4202AE60.6000706@coretech.co.nz>
Comments: In-reply-to Mark Kirkwood <markir@coretech.co.nz>
	message dated "Fri, 04 Feb 2005 12:06:08 +1300"
Date: Thu, 03 Feb 2005 18:18:24 -0500
Message-ID: <5980.1107472704@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>

Mark Kirkwood <markir@coretech.co.nz> writes:
> Glancing over these as I was doing the FreeBSD patch, I noticed some
> scope for modernization there plus a possible error to correct:

> i) we could standardize the change method to use sysctl instead of
> echo'ing things into /proc/kernel/* structures (unless there is some
> reason for this to be preferable?)

How far back in Linux history does that work?  It would be bad to remove
instructions needed for versions that people are still using.  But yeah,
if we can standardize on describing sysctl that's probably a good thing,
since it applies to more than one platform.

> ii) we are recommending setting kernel.shmall equal to kernel.shmmax. I
> think this is incorrect or strange anyway :

It does make sense for shmall-in-bytes to exceed shmmax-in-bytes, but
probably not by a factor of 4000 ...

			regards, tom lane