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Date: Sun, 25 Feb 2007 21:10:20 -0800
From: "Kip Macy" <kip.macy@gmail.com>
To: "Jack Vogel" <jfvogel@gmail.com>
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Cc: freebsd-net <freebsd-net@freebsd.org>, Andre Oppermann <andre@freebsd.org>
Subject: Re: improved TSO interface needed
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> LSO is MicroSlop's term for TSO :) As usual, they rename it, and
> next they do something non-standard to er 'differentiate' as the
> euphemism goes...
>
> Kinda what Sun's lawsuit back in the 90s against their Java
> strategy was all about :)
>
> Nevertheless, I don't understand Kip either, when we do TSO there
> is no evidence on the wire, it still has MTU sized packets.  I fail to
> see why I should care about some LSO spec, what does it break?

The stack will send down chains where pkthdr.len > 65536 bytes - I'm
also seeing it send down mbuf chains of 66 mbufs or more. I don't
think all cards can handle an arbitrary number of descriptors being
used for a single packet.

                   -Kip