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From: Alex Merritt <merritt.alex@gmail.com>
Date: Fri, 2 Oct 2015 10:43:12 -0400
Message-ID: <CADK3taL=wd5Uun_E-RJTG-LyrpK6E38PG28HY-GSPm0ATBouQw@mail.gmail.com>
Subject: Explicit superpage allocation
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Hi all,

mmap(2) states with first use of a memory region with backing frames not
yet allocated and an appropriate alignment, the kernel will automatically
use a larger page when given MAP_ALIGNED_SUPER.

Is there a method to explicitly request a specific page size for an
anonymous memory region? I want to perform measurements using 2MB-backed
regions and 1GB-backed regions, but do not want the kernel to make
arbitrary decisions underneath me.

I am using 10.2 and Intel hardware.

Thanks,
Alex