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Date: Mon, 23 Jan 2012 11:38:08 -0800 (PST)
From: Hugh Dickins <hughd@google.com>
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To: "Borzenkov, Andrey" <andrey.borzenkov@ts.fujitsu.com>
cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: Transparent huge pages and shmem?
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On Mon, 23 Jan 2012, Borzenkov, Andrey wrote:

> In case of THP enabled kernel - will THP be used for SysV shmem?
> The obvious target is to avoid pre-allocation of huge pages pool
> for databases like Oracle that is required today.

It will one day, yes.  Various people are very interested in THP on
tmpfs/shmem, which serves SysV shm.  But at present THP is limited to
private anonymous pages, and its extension to shared file pages is not
trivial.  I have not heard of anyone making significant progress on
that as yet - but perhaps someone is working on it behind the scenes.

Hugh