From owner-freebsd-net@freebsd.org  Tue Nov  7 17:25:36 2017
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Date: Tue, 07 Nov 2017 12:25:24 -0500
From: Joe Buehler <aspam@cox.net>
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To: Vincenzo Maffione <v.maffione@gmail.com>
CC: FreeBSD Net <freebsd-net@freebsd.org>
Subject: Re: virtio_net / netmap RX dropping frames
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I believe the frame drop is due to the nature of my KVM setup.  There
are large latencies in processing incoming frames due to the vagaries of
the LINUX kernel.  Moving to the RT kernel helped, host tuning is also
needed to eliminate large latencies in processing frames.  There is good
information on real-time KVM on the net that explains how to achieve
what I want.

Joe Buehler