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From: Juli Mallett <jmallett@FreeBSD.org>
Date: Mon, 7 May 2012 17:31:49 -0700
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Cc: freebsd-net@freebsd.org, Vijay Singh <vijju.singh@gmail.com>
Subject: Re: What does adapter->stats.mpc[] report for ixgbe?
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While we're on the subject, I've had some confusion for some time now:

On Mon, May 7, 2012 at 5:25 PM, Jack Vogel <jfvogel@gmail.com> wrote:
> Packets are missed when the receive FIFO has insufficient space to store the
> incoming packet.

This means the on-card FIFO, i.e. the fixed-size FIFO that is divided
into receive and transmit space by the driver, right?  And the
separate "receive no buffers" counter records instances where the
packet made it to the card but there was no buffer associated with a
receive descriptor to write it to?  That has been my interpretation of
the documentation and the numbers I've seen in practice, but I've seen
conflicting interpretations and would much rather hear it from the
horse's mouth :)

Thanks,
Juli.