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Date: Tue, 2 Oct 2007 21:11:05 -0500
From: Olof Johansson <olof@lixom.net>
To: Will Schmidt <will_schmidt@vnet.ibm.com>
Subject: Re: [PATCH] Use 1TB segments
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Hi,

On Tue, Oct 02, 2007 at 01:37:54PM -0500, Will Schmidt wrote:
> [RFC v2] 1TB Segment size support
> 
> From:  <>
> 
> 1TB Segment size support
> 
> This makes the kernel use 1TB segments for all kernel mappings and for
> user addresses of 1TB and above, on machines which support them
> (currently POWER5+ and POWER6).

PA6T supports them as well :)

>                                 We don't currently use 1TB segments
> for user addresses < 1T, since that would effectively prevent 32-bit
> processes from using huge pages unless we also had a way to revert to
> using 256MB segments.

Wouldn't it be possible to stick with 1TB segments for the low range
for 64-bit processes as well, and have them allocate their hugepages
at >1TB?


-Olof