Who wants SACK? (Re: was My planned work on networking stack)

[Brooks Davis]

On Wed, Mar 10, 2004 at 06:23:07PM +0200, Petri Helenius wrote:
> Brooks Davis wrote:
> 
> >For that matter, there are sufficent drops on 10GbE from data errors to
> >insure that two boxes connected back to back won't achieve line speed on
> >a single TCP session.
> >
> Do you have data to back this up or are you just using broadcom chipsets?

I looked for the paper I paraphrased, I'm pretty sure if was one by
Sally Floyd.  I didn't find it, but this paper talks a bit about the
issue on page 7:

http://www.calit2.net/research/labs/features/CACM/CACMDefanti.pdf

The problem is that the BER of a typical optical link is high enough
that the link will almost certantly discard at least one packet before
you get out of slow-start and once that happens it, AIMK means it take
hours or even days to get back up to the top even assuming you don't
lose further packets.  This isn't a problem for most people, but it's
definalty a problem for the HPC community.

-- Brooks

-- 
Any statement of the form "X is the one, true Y" is FALSE.
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