Memory Upgrade issue

bcward · Tux's lil' helper Joined: 20 Jan 2007 Posts: 89

I recently found a very good deal on some ram, so I upgraded to 8gb. I knew (or maybe thought is the better word) that since I was running gentoo x86_64, that I could fully utilize all 8gb. But I seem to be having some issues, so I will explain the experiments I have done, and how things have reacted.

First, I plugged in all 8gb and the system wouldn't boot. The boot process just streamed error messages so fast I couldn't read what they were saying.

Second, I took out 4gb, so I only had 4gb left. I booted the system and everything worked fine, but under /proc/meminfo, I noticed I only had 3gb, even though I should have had 4. I rebooted and found that even the bios only recognized 3gb.

Third, whle I was in the bios I found an option called memory remapping (I think is what it was called) and so I enabled it, and rebooted, and both bios and gentoo recognized all 4gb. Then I proceeded to put in the other 4gb and it recognized 6gb. Why 6 instead of 8 i don't know, but I figured it was better than 3 or 4 so I kind of ignored the issue figuring I'd fiddle with it later.

Then after spending some time actually using the computer (about 5 - 10 minutes) it seemed to have crashed. It didn't accept any user input and the audio sounded like a broken record. I did a hard reboot and it did the same thing again after about the same amont of time.

Is there a kernel option that I need to set for highmem under a 64 bit linux? Or is there a kernel option for the memory remapping feature? Or is there something entirely different that I need to do to get it to recognize all of my ram and then use it properly. Or is it a bios issue? I just dont know.

Just for reference I am running a 2.6.22-r5 kernel, asus p5b mobo, and an into core 2 duo 6600.

hitachi · Posted: Thu Jan 17, 2008 7:39 pm Post subject:

Hi,

you should have a look in the man for your motherboard. Maybe the board will not support that much ram.

Sometimes the output is not what you like to see. For example:

bcward · Tux's lil' helper Joined: 20 Jan 2007 Posts: 89

Thanks for your ideas, but I am afraid the problem still has not been resolved. I looked and my mobo does support up to 8gb of ram (in theory).

I do see what you are saying in terms of the free -g versus free, but I looked in /proc/meminfo and it gives the exact amount of ram the system has. What I had reported before was correct.

I just took out 4 of the 8gb I had in, and now the system sees all 4gb. Before I enabled memory remapping in ram, it only recognized 3gb, so by enabling that option I got another gb. The system seems to be running fine now, so that leads me to believe that gentoo doesn't have a problem with this memory remapping feature, but rather the actual amount of ram that I have.

I couldn't seem to find any highmem options in the kernel config, could someone specify how I could find it?

Thanks again for your help.

hitachi · Posted: Fri Jan 18, 2008 9:53 pm Post subject:

When reading another threat I found an idee you may also use. Try booting from the live CD and see what is happening.
https://forums.gentoo.org/viewtopic-t-644894-highlight-highmem.html