From: "Marcelo V. Lima" <[EMAIL PROTECTED]>

mas nao eh o PAE que habilita high memory?

O PAE habilita o acesso a mais de 32bits de memoria (4GB RAM) e tem varios problemas e limites na sua implementação.

Esse assunto surgiu na lista do DFBSD recentemente, veja abaixo:

On Wed, Jun 08, 2005 at 10:18:02AM -0700, Matthew Dillon wrote:
>     We don't have any PAE code in DragonFly.  I don't currently intend
>     to add it... it's a severe hack.i [snip]

Let me elaborate a bit more on this. PAE makes the kernel work a lot
harder, because the kernel can't access all memory at the same time.
This means that you have to be a lot more careful when accessing
memory, since it might currently not be present.

It also adds the general problem of 64bit machines in that many PCI
bus master devices still only support "low" memory (below 4GB). For
this reason you often don't gain anything from using it e.g. for
buffer caching, since you have to copy it into the low memory or
reverse before doing IO.


Luiz - loos
PS: essa mensagem do dfbsd precisa de duas traduções, uma para o portugues e outra para linguagem de usuario... isso que é falar dificil...

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