Re: x86 Page Sizes

From: Peter Svensson (
Date: Thu Jun 27 2002 - 01:35:05 EST

On 26 Jun 2002, Robert Love wrote:

> Kernel has 4K pages in user and kernel space. It is the same address
> space and segment, just uses MMU protection.
> x86 does 4K pages.

The x86 cpus can use 4K or 4M pages in the hardware. The 4M pages are
restricted to the kernel in Linux due to various problems. This has been
discussed on this list a while ago. The thread was called "Have the 2.4
kernel memory management problems on large machines been fixed?" the last
time around.

4M pages are useful to minimize tlb misses which can be costly for some


Peter Svensson      ! Pgp key available by finger, fingerprint:
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