Re: Kernel Development & Objective-C

Gilboa Davara
2007-12-05T10:32:01Z

On Tue, 2007-12-04 at 12:50 -0500, Lennart Sorensen wrote:
> On Mon, Dec 03, 2007 at 02:35:31PM +0200, Gilboa Davara wrote:
> > Intel's newest dual 10GbE NIC can easily (?) throw ~14M packets per
> > second. (theoretical peak at 1514bytes/frame)
> > Granted, installing such a device on a single CPU/single core machine is
> > absurd - but even on an 8 core machine (2 x Xeon 53xx/54xx / AMD
> > Barcelona) it can still generate ~1M packets/s per core.
>
> 10GbE can't do 14M packets per second if the packets are 1514 bytes. At
> 10M packets per second you have less than 1000 bits per packet, which is
> far from 1514bytes.
>
> 10Gbps gives you at most 1.25GBps, which at 1514 bytes per packet works
> out to 825627 packets per second. You could reach ~14M packets per
> second with only the smallest packet size, which is rather unusual for
> high throughput traffic, since you waste almost all the bytes on
> overhead in that case. But you do want to be able to handle at least a
> million or two packets per second to do 10GbE.

... I corrected my math in the second email. [1]

Never the less, a VOIP network (E.g. G729 and friends) can generate the
maximum number of frames allowed on 10GbE Ethernet which is, AFAIR just
below 15M -per- port. (~29M on a dual port card)

While I doubt that any non-NPU based NIC can handle such a load, on
mixed networks we're already seeing well-above 1M frames per port.

- Gilboa
[1] http://lkml.org/lkml/2007/12/3/69