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Date: Wed, 22 Jan 2014 18:52:00 -0500
From: Garrett Wollman <wollman@freebsd.org>
To: net@freebsd.org
Subject: Use of contiguous physical memory in cxgbe driver
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At this point everyone is well aware that requiring contiguous
physical page when the hardware can do scatter-gather is a very bad
idea.  I have a new server under test (running 9.2) which uses Chelsio
rather than Intel 10G Ethernet controllers.  We fixed the Intel driver
not to use more-than-page-sized jumbo mbufs.  Can anyone say with
certainty whether the Chelsio hardware actually requires
physically-contiguous allocations for jumbo frames?  Has this already
been fixed in a more recent driver?  (The hardware is identified
specifically as a T420-CR.)

-GAWollman