On 11/5/07, Ed L. Cashin <ecashin@coraid.com> wrote:
On Mon, Nov 05, 2007 at 10:30:28AM -0600, Jon Nelson wrote:
>     Performance between A and C is always reasonable.

That appears to contradict the rest of your email.

Very true - I later corrected myself.

>     What is going on here? Why is performance so bad from A->C or C->A ?
> 5.4 seconds to send 512K. Does anybody have any ideas?

It could be a bad network cable or a bad network switch, or bad
network settings.  In general, the only way to tell is with analysis,
focusing on each part of the larger system in succession.

I've tried all kinds of variations - this same setup worked fine for over 2 years now, I've achieved up to 90MiB/s (when I had gig-e set up here) using the same cable, switch, and machines. The only difference now is the motherboard, server NIC, and O/S (openSUSE 10.3 vs. 10.2)

I'll do more investigation and see what I can turn up. Sorry to have bothered!