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Date: Fri, 25 Oct 2013 02:29:37 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: "Theodore Ts'o" <tytso@mit.edu>
Cc: "Artem S. Tashkinov" <t.artem@lycos.com>, torvalds@linux-foundation.org,
        fengguang.wu@intel.com, linux-kernel@vger.kernel.org
Subject: Re: Disabling in-memory write cache for x86-64 in Linux II
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On Fri, 25 Oct 2013 05:18:42 -0400 "Theodore Ts'o" <tytso@mit.edu> wrote:

> What I think would make sense is to dynamically measure the speed of
> writeback, so that we can set these limits as a function of the device
> speed.

We attempt to do this now - have a look through struct backing_dev_info.

Apparently all this stuff isn't working as desired (and perhaps as designed)
in this case.  Will take a look after a return to normalcy ;)