workstation not seeing all 4gigs ? [resolved]

[dirtbag]

hey folks, I just upgraded my workstation from 1 gigs to 4 gigs o memory.. My bios reports all 4 gigs..
lshw shows two 2 gig modules..
top and cat /proc/memory shows only 2.8gigs and im wondering why..
I was looking at my kernel configuration and I saw something that I never noticed before.
theres a config for 1/3 kernel memory split for user/system or something like that.
Im wondering if thats the reason? Is this the optimal (kernel) configuration for me to be using?

-db

[tuber]

I don't know about the user/kernel split, but try setting Processor type and features->High Memory Support to 64GB in your kernel config.

[Ato]

[fangorn]

Do you have a graphics card with 1 GB Memory?

PCI bus needs to map its Memory adresses into the RAM adress space therefore the area down from 4 GB to 4 GB minus video RAM is not accessible.

You can (probably) get around this by setting a "memory hole" in the BIOS of your machine. Then the BIOS maps the memory covered by the PCI bus to the area above 4 GB. If the BIOS works correct, this works without problems. If not, try getting a more recent BIOS version.
_________________
Video Encoding scripts collection | Project page

[MaximeG]

Hi,

Have you set up the "support for high memory" somethingish in your kernel settings ?
This needs to be done if you run a 32bit system with 4 or more gigs of memory.

Regards,
Maxime
_________________
Future is wide open.

[dirtbag]

yes, I do have an embedded video card thats sucking up 256 megs i believe..


jason@badman ~ $ cat /proc/meminfo
MemTotal: 2855744 kB
MemFree: 1721660 kB
Buffers: 282400 kB
Cached: 428940 kB
SwapCached: 0 kB
Active: 576796 kB
Inactive: 470860 kB
Active(anon): 355692 kB
Inactive(anon): 0 kB
Active(file): 221104 kB
Inactive(file): 470860 kB
Unevictable: 48 kB
Mlocked: 48 kB
HighTotal: 1974024 kB
HighFree: 1198988 kB
LowTotal: 881720 kB
LowFree: 522672 kB
SwapTotal: 987988 kB
SwapFree: 987988 kB
Dirty: 96 kB
Writeback: 0 kB
AnonPages: 336356 kB
Mapped: 99552 kB
Slab: 64348 kB
SReclaimable: 57956 kB
SUnreclaim: 6392 kB
PageTables: 1800 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
WritebackTmp: 0 kB
CommitLimit: 2415860 kB
Committed_AS: 948576 kB
VmallocTotal: 122880 kB
VmallocUsed: 47612 kB
VmallocChunk: 73204 kB
DirectMap4k: 20472 kB
DirectMap4M: 888832 kB
jason@badman ~ $


*-memory:0
description: System Memory
physical id: 29
slot: System board or motherboard
size: 4GiB
*-bank:0
description: DIMM Synchronous 800 MHz (1.2 ns)
product: PartNum0
vendor: Manufacturer0
physical id: 0
serial: SerNum0
slot: DIMM0
size: 2GiB
width: 64 bits
clock: 800MHz (1.2ns)
*-bank:1
description: DIMM Synchronous 800 MHz (1.2 ns)
product: PartNum1
vendor: Manufacturer1
physical id: 1
serial: SerNum1
slot: DIMM1
size: 2GiB
width: 64 bits
clock: 800MHz (1.2ns)

in the kernel config, under High Memory Support
(X) 4GB

under Memory split (3G/1G user/kernel split) --->
(X) 3G/1G user/kernel split

-db

[Master Shake]

In your kernel config you need to have selected the 64GB option for memory. Also it wouldn't hurt to run a 64-bit OS if you're trying to use that much memory. I know this isn't windows (and I'm thankful) so you don't NEED to install a 64-bit OS but I do know that there are performance losses with enabling the 64GB option.
_________________
System Specs:
64-bit gentoo linux
Q6600 @ 3.2Ghz
P35 Chipset
4 Gigs 800mhz 4-4-4-12
Nvidia GeForce 8800 GTX @ 630mhz

[dirtbag]

enabled the 64Gig option in the kernel.. recompiled and reboot!


jason@badman ~ $ head /proc/meminfo
MemTotal: 3885764 kB
MemFree: 3260524 kB
Buffers: 47488 kB
Cached: 312564 kB
SwapCached: 0 kB
Active: 425300 kB
Inactive: 144352 kB
Active(anon): 211704 kB
Inactive(anon): 0 kB
Active(file): 213596 kB
jason@badman ~ $ uname -a
Linux badman 2.6.31-tuxonice #1 SMP Fri Oct 16 10:12:40 EDT 2009 i686 AMD Athlon (tm) 64 X2 Dual Core Processor 4000+ AuthenticAMD GNU/Linux
jason@badman ~ $

thanks folks.