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Gompho
27th August 2008, 02:15 AM
Ok so im kinda stumped on this. My feeling is that this is normal behavior for FC9 but it would be great if I could get some confirmation. This server Im running has 5 gigs of ram in total. The correct amount (5 gigs) shows up in the bios it also shows up in dmidecode.

#dmidecode --type memory | grep Size
Size: 1024 MB
Size: 1024 MB
Size: 1024 MB
Size: 1024 MB
Size: 512 MB
Size: 512 MB
Also it shows up in ipmi

#ipmitool fru | grep Size
Memory Size : 512 MB
Memory Size : 512 MB
Memory Size : 1024 MB
Memory Size : 1024 MB
Memory Size : 1024 MB
Memory Size : 1024 MB
Now heres where it doesn't show up

#head -1 /proc/meminfo
MemTotal: 3893696 kB
in case your also wondering heres the swap info

#cat /proc/swaps
Filename Type Size Used Priority
/dev/sda2 partition 2562356 132 -1

I know this ram is good because my sel logs aren't even flagging it at post neither does a diagnostic cd running memory tests. So my question is pretty simple. Is this normal or am I missing something?

Can anyone please help me out with this. It would be greatly appreciated.

PatMcLJr
27th August 2008, 02:26 AM
my guesses

32 bit OS with too much memory?

some 64 bit OS flaw that needs a bug report?

I have read that the 32 OS have a limit right about the amount shown in the MemTotal you show.

That's my guesses.
Best of Luck,
Pat Jr.

Gompho
27th August 2008, 02:41 AM
That the thing. I was thinking about that but this is a dual cpu system with hyper threading. It shows up as 4 cpu's but really theres only 2 physical cpu's


#cat /proc/cpuinfo | grep processor
processor : 0
processor : 1
processor : 2
processor : 3


#dmidecode --type processor (snippit)
Processor Information
Socket Designation: CPU 1
Family: Xeon
Manufacturer: Intel Corporation
Status: Populated, Enabled

Processor Information
Socket Designation: CPU 2
Family: Xeon
Manufacturer: Intel Corporation
Status: Populated, Enabled

Any more ideas are welcomed

PatMcLJr
27th August 2008, 02:59 AM
not to insult you or show any disrespect,
do you have the 64 bit version of fedora installed?

I don't recall the command to see the version or how to check. Sorry, this is beyond my skills.

Best of Luck,
Pat Jr.

marko
27th August 2008, 03:16 AM
uname -m

if it says x86_64 --> then it's 64 bit
if i386 or i686 --> 32 bit

I think the problem is you have too much memory like Pat says, you should install the
64bit Fedora. Also, with a 32bit OS, the pci hardware takes a large bite out of address space you can use downwards from 4GB. The easiest fix is to use the 64 bit version of the OS. Some BIOSs support "memory hoisting" which is a trick to reclaim this.

JN4OldSchool
27th August 2008, 03:20 AM
If you are running 32 bit then just install the kernel-PAE package and reboot making sure you boot into that kernel. All your RAM will be showing. :)

Gompho
27th August 2008, 03:24 AM
Im not insulted at all. I appreciate the help. Its a 32 bit kernel running on dual 32 bit cpu's

#>uname -r
2.6.25.14-108.fc9.i686

Is his really because I have a 32 bit kernel. If it is then I guess im going to have to read up on PAE. Another question might be. Even though its not showing up in meminfo is it still being used?

Gompho
27th August 2008, 03:31 AM
Thanks for the tremendous Help. I literally opened this thread 10 minutes ago and have already received a lot of valuable information. This really goes to show the power of a community resource like this. I will install bring the system down on the weekend and check to see if I can find any reference to "memory hoisting" in the bios like marko suggested if not I will try and implement PAE like JN4OldSchool suggested. Hopefully with all this help I will be able to find a resolution.

marko
27th August 2008, 04:13 AM
memory hoisting is more officially called "memory remapping" or "memory hole remapping" if that helps, google shows tons of info on this subject.