[nsp] Frame bursting

sthaug at nethelp.no sthaug at nethelp.no
Mon Mar 31 22:47:12 EST 2003

> > So, if I understand correctly, a normal (12-byte)  
> > inter-frame gap isn't necessarily going to have a huge
> > impact, even on 1500-byte frames. Going to jumbo frames
> > won't make a noticeable difference (0.8% efficiency loss vs
> > 0.1% efficiency loss).
> Its not the impact on the network, its the impact on the routers. Large 
> packets = fewer interrupts/sec = less cpu load.

At gigabit speeds one would hope you have routers with hardware (ASIC)
based forwarding. If that is the case, the most important feature of
jumbo frames is fewer interrupts and reduced CPU load on the *hosts*.

Reality check: 1 Gbps = 1000000000/(1538*8) pps = 81274 pps at normal
frame sizes, and 1000000000/(9038*8) pps = 13830 pps with 9000 byte
jumbo frames.

Steinar Haug, Nethelp consulting, sthaug at nethelp.no

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