Trustix Linux Not Recognizing RAM greater than 4 GB

[lsaishanker]

Hello Friends,

We are using DELL POWEREDGE 6650 Server for our main Database Mysql running on TRUSTIX 2.2 OS.
we have upgraded our RAM from 4GB to 14 GB, Linux recognizes only 4 GB of RAM but it does not recognize the other 10 GB of RAM. The RAM is recognized by the HW through BIOS.
I also tried installing linux trustix version 3.0 but did not working even with that.


Is there a upgrade patch OS available for huge mem kernel, or we need to recompile the the Kernel.

If yes, any documentation or help is available for that.

Thanks in advance
Sai.

[carlosponti]

you will have to let everyone here know what kernel you are running. as far as i know there is a 4gb memory limit in 32 bit cpus. post your hardware specs as well for someone to help you.

[lsaishanker]

We have DELL Power EDGE 6650,
here is the link to the hardware specifications:-

http://maat.med.cornell.edu/66x0_specs.pdf
Hope that helps.
Thanks,
Sai.

[AlexK]

are the Xeons 32 bit or 64-bit? Like carlosponti said, 32-bit processors are limited to 4GB of RAM. Otherwise, I'd contact Dell and ask them how it is possible to load 14GB RAM onto such a system. They are also recommending RH as a OS they can load, perhaps you should talk to them about that...

[Zelmo]

You're going to need to recompile the kernel unless there's a pre-built kernel available for >4GB machines.
There's a kernel config option called "High Memory Support" with three options: less than 1GB, between 1 and 4GB, and greater than 4GB. You need to have the third one enabled, but it sounds like the second one was compiled into the kernel. Unfortunately because it's compiled in, there's no userspace fix; a recompile would be required in this case.

If you want to check your current kernel config to see if that's the problem, look at /boot/config-<your_kernel_version> and find a few lines starting with CONFIG_HIGHMEM. All should be commented out (line starts with #) except the one that's actually enabled.

[Game master pro]

Why the hell did you get 14gb of ram?

[AlexK]

Why the hell did you get 14gb of ram?

why the hell not? The OP is running a server after all, so it would make sense to get more RAM.

[lsaishanker]

Hello Friends,

Thank you for taking interest in my question. I am extremely sorry that i forgot to mention one point.
Actually the machine we are using had 8 GB of ram and was very much functional.But then we had some bad sectors in the hard disk and there was some problem in the motherboard.SO the DELL Tech guy came and replaced the motherboard and upgraded the ram.
So I guess as the machine processor was working fine with 8GB so it must also be fine with 14 GB except we are missing out some files I guess!

Thanks,
Sai.

[lsaishanker]

Hello Friends,
I figured it out - had to recomile the kernel with specific options.
Thank you everybody for all the support.
Sai.

[lsaishanker]

Hello Friends,
I figured it out - had to recompile the kernel with specific options.
Thank you everybody for all the support.
Sai.