Kernel-PAE and where is my 4Gb ?

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dtobal
Posts: 1
Joined: 2012/03/04 12:47:07

Kernel-PAE and where is my 4Gb ?

Post by dtobal » 2012/03/04 12:51:58

Hi All,

I need some help.... my IBM server has 4Gb Ram, and when I use top, or webmin, I just can see 2Gb.
I already installed kernel-PAE and add mem=4096M to my grub.conf .

I can see the memory installed in my hardware info that I am sending below. Did I forget anything?

Please! This memory is missing and resulting in bad performance!

My Centos is 5.5.

Thanks,
Denilson


[root@ipbx tmp]# more 030312.txt
ipbx.ssc.br
description: Tower Computer
product: System x3200 M3 -[7328AC1]- (XxXxXxX)
vendor: IBM
version: 05
serial: TR01AN4
width: 32 bits
capabilities: smbios-2.5 dmi-2.5 smp-1.4 smp
configuration: boot=normal chassis=tower cpus=1 family=System X sku=XxXxXxX
uuid=08B89A10-E5B3-11E0-8F0B-E41F1393703F
*-core
description: Motherboard
product: System Planar Card
vendor: IBM
physical id: 0
version: SIT
serial: 19L5JN
slot: Rear Bottom
*-cpu
description: CPU
product: Intel(R) Xeon(R) CPU X3430 @ 2.40GHz
vendor: Intel Corp.
physical id: 1
bus info: cpu@0
version: 6.14.5
serial: 0001-06E5-0000-0000-0000-0000
slot: Node 1 Socket 1
size: 1197MHz
capacity: 4GHz
width: 64 bits
clock: 505MHz
capabilities: x86-64 boot fpu fpu_exception wp vme de pse tsc msr pae
mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss h
t tm pbe nx rdtscp constant_tsc nonstop_tsc pni monitor ds_cpl vmx smx est tm2 s
sse3 cx16 xtpr sse4_1 sse4_2 popcnt lahf_lm _8_ cpufreq
configuration: cores=4 enabledcores=4 id=4 threads=4

*-memory
description: System Memory
physical id: 5
slot: System board or motherboard
size: 4GiB
*-bank:0
description: DIMM 1333 MHz (0.8 ns)
product: M393B5673FH0-CH9
vendor: Samsung
physical id: 0
serial: AA34F404
slot: DIMM01
size: 2GiB
width: 64 bits
clock: 1333MHz (0.8ns)
*-bank:1
description: DIMM 1333 MHz (0.8 ns)
product: 18JSF25672PDZ1G4G1
vendor: Micron
physical id: 1
serial: 892E89E0
slot: DIMM02
size: 2GiB
width: 64 bits

*-firmware
description: BIOS
vendor: IBM Corp.
physical id: 13
version: -[GYE152AUS-1.12]-
date: 06/29/2011
size: 1MiB
capacity: 4032KiB
capabilities: pci pnp upgrade shadowing cdboot bootselect edd int13flo
ppynec int13floppytoshiba int13floppy360 int13floppy1200 int13floppy720 int13flo
ppy2880 int5printscreen int9keyboard int14serial int17printer int10video acpi us
b ls120boot zipboot biosbootspecification netboot
*-pci
description: Host bridge
product: Clarksfield/Lynnfield DMI
vendor: Intel Corporation
physical id: 100
bus info: pci@0000:00:00.0
version: 11
width: 32 bits
clock: 33MHz

[root@ipbx tmp]# more dmidecode.txt
# dmidecode 2.10
SMBIOS 2.5 present.
60 structures occupying 2244 bytes.
Table at 0x7F6B9000.

Handle 0x0000, DMI type 38, 16 bytes
IPMI Device Information
Interface Type: KCS (Keyboard Control Style)
Specification Version: 2.0
I2C Slave Address: 0x10
NV Storage Device: Not Present
Base Address: 0x0000000000000C92 (I/O)

Handle 0x0001, DMI type 4, 40 bytes
Processor Information
Socket Designation: Node 1 Socket 1
Type: Central Processor
Family: Xeon
Manufacturer: Intel(R) Corporation

PAE (Physical address extension)

Version: Intel(R) Xeon(R) CPU X3430 @ 2.40GHz
Core Enabled: 4
Thread Count: 4
Characteristics:
64-bit capable

Handle 0x0002, DMI type 7, 19 bytes
Cache Information
Socket Designation: Internal Cache Level 3
Configuration: Enabled, Not Socketed, Level 3
Operational Mode: Write Back
Location: Internal
Installed Size: 8192 kB
Maximum Size: 8192 kB
Supported SRAM Types:
Asynchronous
Installed SRAM Type: Asynchronous
Speed: Unknown
Error Correction Type: Single-bit ECC
System Type: Unified
Associativity: 16-way Set-associative

Handle 0x0003, DMI type 7, 19 bytes
Cache Information
Socket Designation: Internal Cache Level 1
Configuration: Enabled, Not Socketed, Level 1
Operational Mode: Write Back
Location: Internal
Installed Size: 32 kB
Maximum Size: 32 kB
Supported SRAM Types:
Asynchronous
Installed SRAM Type: Asynchronous
Speed: Unknown
Error Correction Type: Single-bit ECC
System Type: Data
Associativity: 8-way Set-associative

Handle 0x0004, DMI type 7, 19 bytes
Cache Information
Socket Designation: Internal Cache Level 2
Configuration: Enabled, Not Socketed, Level 2
Operational Mode: Write Back
Location: Internal
Installed Size: 256 kB
Maximum Size: 256 kB
Supported SRAM Types:
Asynchronous
Installed SRAM Type: Asynchronous
Speed: Unknown
Error Correction Type: Single-bit ECC
System Type: Unified
Associativity: 8-way Set-associative

Handle 0x0005, DMI type 16, 15 bytes
Physical Memory Array
Location: System Board Or Motherboard
Use: System Memory
Error Correction Type: Single-bit ECC
Maximum Capacity: 32 GB
Error Information Handle: Not Provided
Number Of Devices: 6

Handle 0x0006, DMI type 6, 12 bytes
Memory Module Information
Socket Designation: DIMM01
Bank Connections: 0 0
Current Speed: Unknown
Type: DIMM
Installed Size: 2048 MB (Single-bank Connection)
Enabled Size: 2048 MB (Single-bank Connection)
Error Status: OK

Handle 0x0007, DMI type 17, 27 bytes
Memory Device
Array Handle: 0x0005
Error Information Handle: Not Provided
Total Width: 72 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: None
Locator: DIMM01
Bank Locator: BANK01
Type: Other
Type Detail: Unknown
Speed: 1333 MHz
Manufacturer: Samsung
Serial Number: AA34F404
Asset Tag: Unknown
Part Number: M393B5673FH0-CH9

Handle 0x0008, DMI type 6, 12 bytes
Memory Module Information
Socket Designation: DIMM02
Bank Connections: 0 0
Current Speed: Unknown
Type: DIMM
Installed Size: 2048 MB (Single-bank Connection)
Enabled Size: 2048 MB (Single-bank Connection)
Error Status: OK

Handle 0x0009, DMI type 17, 27 bytes
Memory Device
Array Handle: 0x0005
Error Information Handle: Not Provided
Total Width: 72 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: None
Locator: DIMM02
Bank Locator: BANK02
Type: Other
Type Detail: Unknown
Speed: 1333 MHz
Manufacturer: Micron
Serial Number: 892E89E0
Asset Tag: Unknown
Part Number: 18JSF25672PDZ1G4G1

Handle 0x000A, DMI type 6, 12 bytes
Memory Module Information
Socket Designation: DIMM03
Bank Connections: 0 0
Current Speed: Unknown
Type: None

[root@ipbx log]# tail -n500 dmesg |more

3300MB HIGHMEM available.
896MB LOWMEM available.
found SMP MP-table at 0009d140
Memory for crash kernel (0x0 to 0x0) notwithin permissible range
disabling kdump
NX (Execute Disable) protection: active
On node 0 totalpages: 1074176
DMA zone: 4096 pages, LIFO batch:0
Normal zone: 225280 pages, LIFO batch:31
HighMem zone: 844800 pages, LIFO batch:31
DMI 2.5 present.


user-defined physical RAM map:
user: 0000000000010000 - 000000000009d000 (usable)
user: 000000000009d000 - 00000000000a0000 (reserved)
user: 00000000000e0000 - 0000000000100000 (reserved)
user: 0000000000100000 - 000000007d310000 (usable)
user: 000000007d310000 - 000000007d3d4000 (reserved)
user: 000000007d3d4000 - 000000007db72000 (usable)
user: 000000007db72000 - 000000007dc22000 (reserved)
user: 000000007dc22000 - 000000007f68f000 (usable)
user: 000000007f68f000 - 000000007f6df000 (reserved)
user: 000000007f6df000 - 000000007f7df000 (ACPI NVS)
user: 000000007f7df000 - 000000007f7ff000 (ACPI data)
user: 000000007f7ff000 - 000000007f800000 (usable)
user: 000000007f800000 - 0000000080000000 (reserved)
user: 00000000ff800000 - 0000000100000000 (reserved)
user: 0000000100000000 - 0000000106400000 (usable)
3300MB HIGHMEM available.
896MB LOWMEM available.
found SMP MP-table at 0009d140
Memory for crash kernel (0x0 to 0x0) notwithin permissible range
disabling kdump
NX (Execute Disable) protection: active
On node 0 totalpages: 1074176
DMA zone: 4096 pages, LIFO batch:0
Normal zone: 225280 pages, LIFO batch:31
HighMem zone: 844800 pages, LIFO batch:31
DMI 2.5 present.
DMI: IBM System x3200 M3 -[7328AC1]-/System Planar Card, BIOS -[GYE152AUS-1.12]- 06/29/2011
Using APIC driver default

[root@ipbx log]# uname -a
Linux 2.6.18-274.18.1.el5PAE #1 SMP Thu Feb 9 13:25:50 EST 2012 i686 i686 i386 GNU/Linux


title CentOS (2.6.18-274.18.1.el5PAE)
root (hd0,0)
kernel /vmlinuz-2.6.18-274.18.1.el5PAE ro root=/dev/VolGroup00/LogVol00 mem=4196M rhgb quiet
initrd /initrd-2.6.18-274.18.1.el5PAE.img

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TrevorH
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Posts: 33202
Joined: 2009/09/24 10:40:56
Location: Brighton, UK

Re: Kernel-PAE and where is my 4Gb ?

Post by TrevorH » 2012/03/04 13:41:12

First, I would remove the mem=4196M parameter as it should not be required. For a start it is wrong - you don't have 4196MB installed, you have 4096. It'll also come back and bite you in the rear end when you add more memory to your machine later and wonder why it isn't seen.

Second, I can see no evidence that the 4GB is not being seen. The kernel messages clearly show it being recognised

[quote]
3300MB HIGHMEM available.
896MB LOWMEM available.
[/quote]

I see nothing in your output that says 2GB except on the sizes of the individual DIMMs installed and you have 2 of those which is 4GB.

pschaff
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Kernel-PAE and where is my 4Gb ?

Post by pschaff » 2012/03/05 00:56:38

[quote]
dtobal wrote:
...
My Centos is 5.5. ...
[/quote]
Like Trevor I see no evidence of a memory issue; however, don't use obsolete/unsupported releases - 5.7 is the current release and 5.8 is in QA; however your kernel version indicates you may be mistaken.

If more help is needed after verifying that you are current with "yum update" then please [url=http://www.centos.org/modules/newbb/viewtopic.php?topic_id=28723&forum=54]provide more information about your system[/url] by running "./getinfo.sh" and showing us the output file.

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