ethernet and switches, was Re: [rescue] Mozilla Firefox

[Nathan Raymond]

On Fri, 23 Apr 2004, Joshua Boyd wrote:

> I wonder how much inappropriate legacy stuff is really left inside of
> GigE.

The CPU speed limits gigabit ethernet performance because of the
processing overhead. Standard ethernet packets are a maximum of 1,500
bytes long, which means a computer must process more than 80,000 packets
every second to achieve gigabit ethernet's full throughput. Many systems
can only process about a fifth of that, limiting performance to less than
100 Mbps in a lot of scenarios. To circumvent this problem, gigabit
ethernet supports larger packets called jumbo frames, which can be up to
9,000 bytes each. However, not every ethernet card/driver supports jumbo
packets, and not every gigabit switch supports jumbo packets, and as far
as I know it's not something that's turned on by default in cards that do
support it.

> Unless I luck out on a switch, I don't expect to ever be able to afford
> that, and that seems to leave only GigE.

I think that a gigabit ethernet network with cards and drivers that have
jumbo frames enabled, and switches that support jumbo frames, would
address one of the last roadblocks to making ethernet decent.

--
Nathan Raymond