From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff Moyer <jmoyer@redhat.com>
Subject: O_DIRECT on tmpfs (again)
Date: Tue, 27 Nov 2012 11:03:03 -0500
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To: Hugh Dickins <hughd@google.com>
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Hi Hugh and others,

In 2007, there were some discussions on whether to allow opens to
specify O_DIRECT for files backed by tmpfs.[1][2] On the surface, it
sounds like a completely crazy thing to do.  However, distributions like
Fedora are now defaulting to using a tmpfs /tmp.  I'm not aware of any
applications that open temp files using O_DIRECT, but I wanted to get
some new discussion going on whether this is a reasonable thing to
expect to work.

Thoughts?

Cheers,
Jeff

[1] https://lkml.org/lkml/2007/1/4/55
[2] http://thread.gmane.org/gmane.linux.kernel/482031