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From: Rafael Ganascim <rganascim@gmail.com>
To: freebsd-net@freebsd.org
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Subject: Igb driver - header split feature
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Hi list,

I was looking in the igb driver that I use on some Intel nics
(dualport and quadport gigabit) and in the source code, the feature:

/*
** Header split causes the packet header to
** be dma'd to a seperate mbuf from the payload.
** this can have memory alignment benefits. But
** another plus is that small packets often fit
** into the header and thus use no cluster. Its
** a very workload dependent type feature.
*/

Somebody is using this feature? What's the results?

I think that this feature can be helpfull to improve the performance,
allowing the processing of the packet headers more fastest (pfills,
routing, etc). Is this true?

Thanks in advance.

Rafael