"H. Peter Anvin" wrote:

Ravi K wrote:

quoted

Hi,
  The configuration help for HIGHMEM feature on i386
platform states that 'Linux can use up to 64 Gigabytes
of physical memory on x86 systems'. I see a problem
with this:
 - page structures needed to support 64GB would take
up 1GB memory (64 bytes per page of size 4k)

64GB is physical memory, not virtual memory.

And at approx. 64 bytes per strct page in mem_map, that's
1G worth of page structs, which is Ravi's point.

Cheers,

-- Joe
"I should like to close this book by sticking out any part of my neck
 which is not yet exposed, and making a few predictions about how the
 problem of quantum gravity will in the end be solved."
 --- Physicist Lee Smolin, "Three Roads to Quantum Gravity"
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