2002-01-25 01:05:27

by ivan

[permalink] [raw]
Subject: Physical memory versus detected memory 2.4.7-10


Dear list users.

My server detects less memory than it available.

Available memory according to the BIOS 4049MB.

System sees only 3.7GB ???
Mem: 3799580K av, 1606816K used, 2192764K free, 468K shrd, 376972K buff
Swap: 8192992K av, 0K used, 8192992K free 1037532K cached


OS RedHat 2.7 standard kernel.
Linux atlas.es.usyd.edu.au 2.4.7-10smp #1 SMP Mon Dec 10 13:08:57 EST 2001 i686 unknown

Hardware PowerEdge 4400.
( supports 4GB )

Additional problem:
random crushes, trying to to find out why.

Questions : 1) Any comments on why top only shows 3.7 Gb are welcome.


Thank you.
================================================================================

Ivan Teliatnikov,
F05 David Edgeworth Building,
Department of Geology and Geophysics,
School of Geosciences,
University of Sydney, 2006
Australia

e-mail: [email protected]
ph: 061-2-9351-2031 (w)
fax: 061-2-9351-0184 (w)

===============================================================================



2002-01-25 01:20:31

by Ken Brownfield

[permalink] [raw]
Subject: Re: Physical memory versus detected memory 2.4.7-10

Well, I don't know about that specific machine, but HP LP6000 boxes
reserve 700MB (!) for PCI hot-plug support. So my 4GB boxes are
actually 3.3GB boxes. Can't override it, says HP. They wouldn't refund
70% of the price of a 1GB stick, either. ;)

I suspect what you're seeing is along the same lines; perhaps PCI
hotplug or some other reservation that may be tweakable in the PowerEdge
BIOS. Dell may or may not be able to help.

FWIW; good luck,
--
Ken.
[email protected]

On Fri, Jan 25, 2002 at 12:05:10PM +1100, ivan wrote:
|
| Dear list users.
|
| My server detects less memory than it available.
|
| Available memory according to the BIOS 4049MB.
|
| System sees only 3.7GB ???
| Mem: 3799580K av, 1606816K used, 2192764K free, 468K shrd, 376972K buff
| Swap: 8192992K av, 0K used, 8192992K free 1037532K cached
|
|
| OS RedHat 2.7 standard kernel.
| Linux atlas.es.usyd.edu.au 2.4.7-10smp #1 SMP Mon Dec 10 13:08:57 EST 2001 i686 unknown
|
| Hardware PowerEdge 4400.
| ( supports 4GB )
|
| Additional problem:
| random crushes, trying to to find out why.
|
| Questions : 1) Any comments on why top only shows 3.7 Gb are welcome.
|
|
| Thank you.
| ================================================================================
|
| Ivan Teliatnikov,
| F05 David Edgeworth Building,
| Department of Geology and Geophysics,
| School of Geosciences,
| University of Sydney, 2006
| Australia
|
| e-mail: [email protected]
| ph: 061-2-9351-2031 (w)
| fax: 061-2-9351-0184 (w)
|
| ===============================================================================
|
|
| -
| To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
| the body of a message to [email protected]
| More majordomo info at http://vger.kernel.org/majordomo-info.html
| Please read the FAQ at http://www.tux.org/lkml/

2002-01-25 01:37:39

by Jeff Chua

[permalink] [raw]
Subject: Re: Physical memory versus detected memory 2.4.7-10


On Fri, 25 Jan 2002, ivan wrote:
> My server detects less memory than it available.
> Available memory according to the BIOS 4049MB.
>
> System sees only 3.7GB ???
> Mem: 3799580K av, 1606816K used, 2192764K free, 468K shrd, 376972K buff
> Swap: 8192992K av, 0K used, 8192992K free 1037532K cached

I think you need to recompile the kernel to support 64GB mem.

You current config seems to support up to 4GB only (but it is a bit
less than 4GB). I had a similar problem where I had 1GB, but saw only
9xxGB.

Jeff


2002-01-25 01:39:19

by Jeff Chua

[permalink] [raw]
Subject: Re: Physical memory versus detected memory 2.4.7-10


On Fri, 25 Jan 2002, ivan wrote:
> My server detects less memory than it available.
> Available memory according to the BIOS 4049MB.
>
> System sees only 3.7GB ???
> Mem: 3799580K av, 1606816K used, 2192764K free, 468K shrd,
376972K buff
> Swap: 8192992K av, 0K used, 8192992K free 1037532K cached

I think you need to recompile the kernel to support 64GB mem.

You current config seems to support up to 4GB only (but it is a bit
less than 4GB). I had a similar problem where I had 1GB, but saw only
9xxGB.

Jeff


2002-01-28 03:51:13

by Matt Domsch

[permalink] [raw]
Subject: RE: Physical memory versus detected memory 2.4.7-10

> | My server detects less memory than it available.
> |
> | Available memory according to the BIOS 4049MB.
> |
> | System sees only 3.7GB ???
> | Mem: 3799580K av, 1606816K used, 2192764K free, 468K shrd, 376972K
buff
> | Swap: 8192992K av, 0K used, 8192992K free 1037532K cached

The difference is space assigned to PCI cards or reserved for hot-plug PCI
cards. You should be able to run a CONFIG_HIGHMEM64G-enabled kernel (such
as the Red Hat 2.4.x-enterprise kernels instead of the -smp kernel) and be
able to use the remaining memory, at the performance cost of enabling PAE.

Thanks,
Matt

--
Matt Domsch
Sr. Software Engineer
Dell Linux Solutions http://www.dell.com/linux
#1 US Linux Server provider with 24.5% (IDC Dec 2001)
#2 Worldwide Linux Server provider with 18.5% (IDC Dec 2001)