Subject: Re: 4MB pages?
To: None <>
From: Thor Lancelot Simon <>
List: tech-kern
Date: 09/06/2000 12:56:33
On Wed, Sep 06, 2000 at 09:38:22AM -0700, Jason R Thorpe wrote:
> On Wed, Sep 06, 2000 at 08:16:42AM -0700, Matt Thomas wrote:
>  > For memory intensive (mmap large files, etc.) programs, I was wondering whether
>  > it would be useful to have another uvm free page area which contains free 4MB
>  > blocks.  As memory gets freed, as a complete 4MB block is freed it would be
>  > moved to the free 4MB list.
> That's possible... I haven't really looked at that, yet.

Seems to me that the right abstraction is a list of pages of each size
supported by the architecture, and an algorithm that tries to satisfy
allocation requests using the largest page size available.  Otherwise, we're
bound to continue doing special-purpose hacks...

Don't the PAE on the x86 support both 2MB and 4MB pages, at least in Intel's