[Solved] kernel.pae and >3.4GiB RAM

[atolboo]

A total of 6GB RAM is installed in my ASRock P5B-DE as reported by Bios = 6144MB and systeminfo = 6GiB (2x2GiB 64bits + 2x1GiB 64bits).
CPU = Intel(R) Pentium(R) 4 CPU 3.00GHz 64 bits.
According to Synaptic kernel-3.2.18-pclos2.bfs + kernel-3.2.18-pclos2.pae.bfs are installed.
However to my astonishment System Monitor reports only 3.4GiB memory and also GKrellM reports 3486M.
Is there any explanation/solution why the rest of the 6GB ram is not detected by the kernel.pae

[agmg]

Type uname -a in terminal to see what kernel you are using (probably the non-pae).
Don't you have entries for both kernels in grub?

[atolboo]

In /boot/grub/menu.lst there is:

title linux
title 3.2.18-pclos2.bfs
kernel (hd0,0)/boot/vmlinuz-3.2.18-pclos2.bfs BOOT_IMAGE=3.2.18-pclos2.bfs root=UUID=f64de2a8-0327-4722-a874-46bd6523d1
ca quiet nokmsboot vmalloc=256M acpi=on resume=UUID=af2c3a09-33ed-4f10-b7d2-e56f7413e075 splash=silent vga=788
initrd (hd0,0)/boot/initrd-3.2.18-pclos2.bfs.img

and

title 3.2.18-pclos2.pae.bfs
kernel (hd0,0)/boot/vmlinuz-3.2.18-pclos2.pae.bfs BOOT_IMAGE=3.2.18-pclos2.pae.bfs root=UUID=f64de2a8-0327-4722-a874-46
bd6523d1ca quiet nokmsboot vmalloc=256M acpi=on resume=UUID=af2c3a09-33ed-4f10-b7d2-e56f7413e075 splash=silent vga=788
initrd (hd0,0)/boot/initrd-3.2.18-pclos2.pae.bfs.img

uname -a results in:

bash-4.1$ uname -a
Linux localhost.localdomain 3.2.18-pclos2.pae.bfs #1 SMP PREEMPT Thu May 24 05:33:57 CEST 2012 i686 i686 i386 GNU/Linux
bash-4.1$

And still 3.4 GiB according to System Monitor and GKrellM.

[DeBaas]

The default kernel is always the last (re)installed.
A terminal command tells you what kernel is active:
$ uname -r
2.6.38.8-pclos3.pae.bfs
And for an easy way to see your memory:
$ top -c
top - 21:38:44 up  1:03,  3 users,  load average: 0.90, 0.42, 0.26
Tasks: 204 total,   1 running, 203 sleeping,   0 stopped,   0 zombie
Cpu(s):  1.8%us,  0.2%sy,  0.0%ni, 96.9%id,  1.0%wa,  0.0%hi,  0.0%si,  0.0%st
Mem:   4108180k total,  1857700k used,  2250480k free,   273240k buffers
Swap:  4192928k total,        0k used,  4192928k free,   753812k cached

[atolboo]

Result:

bash-4.1$ uname -r
3.2.18-pclos2.pae.bfs

and

bash-4.1$ top -c
top - 21:56:01 up 3 min,  3 users,  load average: 0.49, 0.52, 0.23
Tasks: 154 total,   1 running, 153 sleeping,   0 stopped,   0 zombie
Cpu(s): 11.2%us,  2.2%sy,  0.0%ni, 86.3%id,  0.3%wa,  0.0%hi,  0.0%si,  0.0%st
Mem:   3564512k total,   954108k used,  2610404k free,    33188k buffers
Swap: 14092284k total,        0k used, 14092284k free,   414460k cached

[atolboo]

Additional test result:
I installed Mageia 3 Beta1 x86_64 in another partition with result..

$ uname -a
Linux localhost 3.7.0-desktop-1.mga3 #1 SMP Tue Dec 11 10:59:16 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

and

$ top -c
top - 22:52:42 up 1 min,  3 users,  load average: 1.56, 0.71, 0.26
Tasks: 134 total,   1 running, 133 sleeping,   0 stopped,   0 zombie
Cpu(s): 24.6%us,  7.9%sy,  4.9%ni, 44.4%id, 17.7%wa,  0.0%hi,  0.4%si,  0.0%st
Mem:   3536912k total,  1037452k used,  2499460k free,    25220k buffers
Swap: 14092284k total,        0k used, 14092284k free,   340660k cached

I get the impression that the problem is in the ASRock P5B-DE as this one has the same problem.
Although the bios reports 6GB.
Tomorrow additional tests will follow.

[DeBaas]

Mmm, found in your manual in the BIOS settings
3.4.2 Chipset Configuration
Memory Remap Feature
(Default  disabled)

ENABLE: Allow
remapping of
overlapped PCI memory
above the total
physical memory.
DISABLE: Do not allow
remapping of memory.

I think it should be enabled for pae.
Testing ?

[atolboo]

I think it should be enabled for pae.

Result is
System Monitor is now reporting 5.9GiB.
and top -c

Mem:   6226912k total,   848464k used,  5378448k free,    32588k buffers

 

[DeBaas]

You are welcome