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Message-ID: <4536bb73050725064273cdbb50@mail.gmail.com>
Date: Mon, 25 Jul 2005 19:12:47 +0530
From: VASM <vasm85@gmail.com>
Reply-To: VASM <vasm85@gmail.com>
To: Nix <nix@esperi.org.uk>
Subject: Re: kernel page size explanation
Cc: Jesper Juhl <jesper.juhl@gmail.com>, gbakos@cfa.harvard.edu,
       linux-kernel@vger.kernel.org
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On 7/25/05, Nix <nix@esperi.org.uk> wrote:
> On Mon, 25 Jul 2005, VASM wrote:
> > i had one question
> > does the linux kernel support only one default page size even if the
> > processor on which it is working supports multiple ?
> 
> No. Some architectures have compile-time support for multiple different
> page sizes (e.g. Itanium, SPARC64); many have support for a
> (non-swappable) `large pages) system, and a filesystem backed by huge
> pages. (Often, the kernel is stored in huge pages, to keep the number
> of page table entries wasted by the nonswappable kernel to a minimum.)
> 
> What is *not* presently supported is using multiple page sizes to
> back userspace processes; that size is currently fixed at compile-time,
> even on architectures supporting multiple variably-sized pages.
> 
are there any specific reasons for not using large page size for
userspace processes

> --
> `But of course, GR is the very best relativity for the masses.'
>  --- Wayne Throop
>