RE: 512MB RAM, 860MB swap and out of memory ?
> My Debian Linux 2.0 cannot use more than 460MB sawp :(
There is a similar thread going on on linux-kernel that may be apropos to
your situation.
Basically, what it comes down to is that the way a (stock) Linux kernel
lays out memory, it is unable to address more than approximately 960MB
of memory (I would assume RAM + SWAP, in your case).
I am not sure if the 2.0 series of kernels has any ability to work around
this problem, but the 2.1 series certainly does. In
/usr/src/linux/include/asm-i386/page.h, you will find the following comment
and constant definition:
/*
* This handles the memory map.. We could make this a config
* option, but too many people screw it up, and too few need
* it.
*
* A __PAGE_OFFSET of 0xC0000000 means that the kernel has
* a virtual address space of one gigabyte, which limits the
* amount of physical memory you can use to about 950MB. If
* you want to use more physical memory, change this define.
*
* For example, if you have 2GB worth of physical memory, you
* could change this define to 0x70000000, which gives the
* kernel slightly more than 2GB of virtual memory (enough to
* map all your physical memory + a bit extra for various
* io-memory mappings)
*
* IF YOU CHANGE THIS, PLEASE ALSO CHANGE
*
* arch/i386/vmlinux.lds
*
* which has the same constant encoded..
*/
#define __PAGE_OFFSET (0xC0000000)
-Jon Burchmore
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