Hey Everybody... I've got a really tricky question and I havn't been able to figure out at all whats going on with my system. I recently got a new Pentium 4 system (w/hyperthreading) and 1 GB or Ram, and Installed Mandrake Linux 9.2 on it.

Now heres the thing, I read everywhere that if you have a GB or higher of RAM, I should use the Enterprise Kernel (you get a choice in Mandrake). But I notice when I use the enterprise kernel the memory usage seems to double. Heres I get for mesaurements:

Normal Kernel: 132M used, 771M free. (903 total MB available to Linux)
Enterprise Kernel: 272M used, 759M free (1031 total MB avaailable to Linux)
SMP Kernel: 132M used, 771M free (903 total MB available to Linux)

Now heres the real kicker... I have an extra 512MB that I plugged in (temporarily) bringing my total up to 1.5GB. Windows XP sees it just fine, as well as Linux. But when I plug it in, the memory usage in the Enterprise Linux kernel skyrockets to over 600M. This is really weird since all I'm doing is starting up linux and bringing up KDE System Guard. I'm not running anything that should consume any memory at all. It seems like the more memory I add, the more is reported as being used. Is there anyone here who has noticed this on their system and knows a reason for it?

Fishlet,

I am having the same problem. I am running Mandrake 9.2 enterprise kernel. I have 2GB or RAM. When I bootup almost 1.3GB is used when I check top or free!

Did you ever find an answer?

Vincent

Well I asked around various forums and got lots of replies telling me that it's normal. Apparently Linux preallocates a sum of memory as a percentage of what you got total. I was quite alarmed when I first saw it happen but have since realized that it apparently is available since I can fire up tons of apps with no apparent delay or disk activity.

It's just confusing because of the weird way Linux reports it's memory usage. I really wish someone would fix that in the future because it doesn't make much sense. I havn't tried any 2.6 kernels yet to see if that is still the case. In any case you don't have to worry about the memory going to waste, Linux is actually using it all.