Gentoo Archives: gentoo-user

From:	Volker Armin Hemmann <volkerarmin@××××××××××.com>
To:	gentoo-user@l.g.o
Subject:	Re: [gentoo-user] Kernel doesn't use all of the available memory
Date:	Fri, 10 Dec 2010 15:49:22
Message-Id:	`201012101647.18902.volkerarmin@googlemail.com`
In Reply to:	[gentoo-user] Kernel doesn't use all of the available memory by Helmut Jarausch

1	On Thursday 09 December 2010, Helmut Jarausch wrote:
2	> Hi,
3	>
4	> I see a strange effect which puzzles me.
5	> I have two AMD64 (~amd64) Systems. Both have 8Gb memory installed
6	> as reported by their BIOS as well as by lshw.
7	> One is a somewhat older Opteron, the other one a recent Phenom II.
8	> But the output of 'free -m' differs significantly
9	>
10	> On the Phenom II there a total of 7738 Mb
11	> but on the old Opteron there a total of 6477 Mb only.
12	>
13	> The 2.6.36 kernel is configured nearly identical (just a different SATA
14	> driver).
15	>
16	> Has anybody an idea where this comes from?
17
18	a) bios limitiation. Some bad bios implementations (even from expensive
19	vendors) map the pci space into the 3.5-4gb or 7.5-8gb area. Stupid.
20
21	b) onboard devices.

Subject	Author
Re: [gentoo-user] Kernel doesn't use all of the available memory	Neil Bothwick <neil@××××××××××.uk>