Hi Gurus

I am having an HP server running Oracle DB. Server had 4GB ram which is now upgraded to 6GB. The BIOS detected the full 6GB ram but the OS is showing only 3.5GB. I am not sure where the rest is going and how can I get it back? I want to fully utalize the available resources. Following is the output of free -m command:

total used free shared buffers cached
Mem: 3512 3507 5 536 487 1587
-/+Buf/Ca: 1432 2080
Swp: 2000 1207 792

Sorry if the answer is obvious for you but I am not a linux person. Any help would be appreciated.

RMA

Hi, not familiar with AS, but I have to compile my kernel to support anything > 4GB, most of the vanilla kernels I have only support up to 895MB?? default, I have to compile in support up to 4GB; again I am not sure about your's, just wanted to put that out there. Hope it helps some.


Welcome to Linux Questions!

Thanks for the reply.

Can you please tell me which parameters I should set?

RMA

Will setting "mem" parameter in grub.conf help Linux using all available ram?

Thanks

Hi, I am not sure what AS 2.1 is; however on my desktop when I added 4G ram I had to recompile the kernel to allow HIGH_MEM support. If you have your kernel sources available you should be able to cat the .config file and grep for HIGH_MEM or HIGHMEM, can't remember exactly what it is.

On the other hand, we have Fedora servers at work that we have loaded with 16-32G of ram and never had to recompile a thing.

I am not sure about the grub thing, but I highly doubt it. However I may be wrong.

Hope it helps some.