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Date:   Fri, 15 May 2015 23:53:21 +0200
From:   Ralf Baechle <ralf@linux-mips.org>
To:     Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc:     aleksey.makarov@auriga.com, james.hogan@imgtec.com,
        paul.burton@imgtec.com, david.daney@cavium.com,
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Subject: Re: [PATCH v2] MIPS64: Support of at least 48 bits of SEGBITS
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On Thu, May 14, 2015 at 06:34:43PM -0700, Leonid Yegoshin wrote:

The order 1 allocation for the PGD are concerning me a little.  On a
system under even moderate memory pressure that might become a bit of
a reliability or performance issue.

With 4kB pages we already need order 1 or even 2 allocations for the
allocation of the stack and some folks have reported that to be an issue
so we may have to start using the PUD for very large VA spaces.

  Ralf