Introducing netmap: line-rate packet send/receive at 10Gbit/s

Luigi Rizzo rizzo at
Thu Jun 2 22:15:42 UTC 2011

we have recently worked on a project, called netmap, which lets
FreeBSD send/receive packets at line rate even at 10 Gbit/s with
very low CPU overhead: one core at 1.33 GHz does 14.88 Mpps with a
modified ixgbe driver, which gives plenty of CPU cycles to handle
multiple interface and/or do useful work (packet forwarding, analysis, etc.)

You can find full documentation and source code and even a picobsd image at

The system uses memory mapped packet buffers to reduce the cost of
data movements, but this would not be enough to make it useful or
novel.  Netmap uses many other small but important tricks to make
the system fast, safe and easy to use, and support transmission,
reception, and communication with the host stack.

You can see full details in  documentation at the above link.

Feedback welcome.

  Prof. Luigi RIZZO, rizzo at  . Dip. di Ing. dell'Informazione        . Universita` di Pisa
  TEL      +39-050-2211611               . via Diotisalvi 2
  Mobile   +39-338-6809875               . 56122 PISA (Italy)

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