[rescue] The Practical Guide to FDDI

[Joshua Snyder]

On Fri, 28 Mar 2003, Phil Brutsche wrote:

<snip>

> Fairly certain.  I certainly never could get more than 20MB/sec without
> fudging with the frame size.
>
> Knowing the configuration of the systems you saw would certianly help.

Well, as I remember it was a 1.8Ghz P4 with 256Meg of ram.  It was a sbc
connected to a 66Mhz 64bit pci backplane.  It had two gigabit Ethernet
cards from Alacritech.
http://www.alacritech.com/html/1000x1_copper_accelerator.html

It was running linux (2.4.18) so it didn't take advantage of any of the
special features of the card, as far as linux is concerned it was a normal
gigabit card.  The data was being pushed through system from both Ethernet
cards, so we saw 700Mbit in and out of both interfaces at the same time.
2.8Gbit/sec is not too bad for a pc, the only reason I don't think we saw
a full gigabit both ways is because of the pci bus.  It was just a case of
good hardware + good drivers = good performance.  As I remember enabling
jumbo frames didn't get us anywhere, but that is what I expected.  I don't
know what you are using, but I have found when it comes to linux you need
to be careful what hardware you use.  Many times you get good hardware
and bad drivers, or like in the case of the cheap National Semi cards bad
hardware and bad drivers.  The only problem with the Alacritech cards is
the cost... I have done the same testing with other cards, as far as I can
remember tg3 based cards were the best price/performance doing about
500Mbit and costing about $150.

				josh

p.s. when I was talking about good hardware I was talking about the
Ethernet cards...


>
> I guess I'll have to try it again.
>
> --
>
> Phil Brutsche
> phil at tux.obix.com
> _______________________________________________
> rescue list - http://www.sunhelp.org/mailman/listinfo/rescue