Hi,
Our Debian 3.1 (2.4.27-2-686-smp kernel) server contains (among other things) 4x2GB sticks of RAM giving us a grand total of 8GB, however, free and cat /proc/meminfo sees roughly only 4GB:
output of free:
total used free shared buffers cached
Mem: 3617740 403476 3214264 0 109400 100168
-/+ buffers/cache: 193908 3423832
Swap: 15599104 0 15599104
output of cat /proc/meminfo:
total: used: free: shared: buffers: cached:
Mem: 3704565760 413147136 3291418624 0 112025600 102572032
Swap: 15973482496 0 15973482496
MemTotal: 3617740 kB
MemFree: 3214276 kB
MemShared: 0 kB
Buffers: 109400 kB
Cached: 100168 kB
SwapCached: 0 kB
Active: 143016 kB
Inactive: 95504 kB
HighTotal: 2752256 kB
HighFree: 2614536 kB
LowTotal: 865484 kB
LowFree: 599740 kB
SwapTotal: 15599104 kB
SwapFree: 15599104 kB
I believe this problem can be solved by recompiling the kernel with CONFIG_HIGHMEM64G=y (at the moment, it's commented out and CONFIG_HIGHMEM4G=y instead) as long as I have PAE (Physical Address Extension) enabled (which it is). But before a final decision is to be made by my supervisor as to exactly what is to be done, we want to know if recompiling the kernel is our only option,
or if there are others?
Also, I've read somewhere (sorry, I forgot where), that there some overhead is involved when using the PAE, so I was wondering if anybody has had any experience/comments regarding this or a similar issue, I would like to hear from you.
Cheers,
-Glen
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Glen Yu, B.Eng | 416-739-4861 | glen.yu@ec.gc.ca
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