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Date: Mon, 17 Jun 1996 18:29:56 GMT
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From: James Raynard <fqueries@jraynard.demon.co.uk>
To: noc@nap.net
CC: questions@freebsd.org
In-reply-to: <31C57A40.41C67EA6@inap.net> (message from Operator on Mon, 17
	Jun 1996 10:31:12 -0500)
Subject: Re: Memory restrictions
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> I am running FreeBSD version 2.1.0 Release...The machine has 128MB
> ram...when the machine boots the memory is physically present yet the
> operating system does not seem to see it...
> My question is...Does FreeBSD have a memory limitation...or am I missing
> something...?

It's in the FAQ:-

  8.6.  I have 128 MB of RAM but it seems that the system use only the
  first 64 MB. What's going on ?

  Due to the manner in which FreeBSD gets the memory size from the BIOS,
  it can only detect 16 bits worth of Kbytes in size (65535 Kbytes =
  64MB). If you have more than 64MB, FreeBSD will only see the first
  64MB. To work around this problem, you need to use the kernel option
  specified below. There is a way to get complete memory information
  from the BIOS, but we don't have room in the bootblocks to do it.
  Someday when lack of room in the bootblocks is fixed, we'll use the
  extended BIOS functions to get the full memory information...but for
  now we're stuck with the kernel option.

              options "MAXMEM=<n>"

  Where n is your memory in Kilobytes. For a 128 MB machine, you'd want
  to use 131072

For some reason, this isn't mentioned in the supposedly exhaustive
LINT file.

-- 
James Raynard, Edinburgh, Scotland
james@jraynard.demon.co.uk