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Date: Fri, 8 May 2015 18:14:48 -0700
Message-ID: <CA+55aFzeCiRSbzsX_NfScqF_-1JiVWj62Qo00pRttZp_s3hCVw@mail.gmail.com>
Subject: Re: [PATCH v2 00/10] evacuate struct page from the block layer,
 introduce __pfn_t
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Rik van Riel <riel@redhat.com>
Cc: John Stoffel <john@stoffel.org>, Ingo Molnar <mingo@kernel.org>,
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On Fri, May 8, 2015 at 9:59 AM, Rik van Riel <riel@redhat.com> wrote:
>
> However, for persistent memory, all of the files will be "in memory".

Yes. However, I doubt you will find a very sane rw filesystem that
then also makes them contiguous and aligns them at 2MB boundaries.

Anything is possible, I guess, but things like that are *hard*. The
fragmentation issues etc cause it to a really challenging thing.

And if they aren't aligned big contiguous allocations, then they
aren't relevant from any largepage cases. You'll still have to map
them 4k at a time etc.

                  Linus
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