Date: Mon, 17 Jun 1996 18:29:56 GMT From: James Raynard <fqueries@jraynard.demon.co.uk> To: noc@nap.net Cc: questions@freebsd.org Subject: Re: Memory restrictions Message-ID: <199606171829.SAA12121@jraynard.demon.co.uk> In-Reply-To: <31C57A40.41C67EA6@inap.net> (message from Operator on Mon, 17 Jun 1996 10:31:12 -0500)
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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
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