tcp troughput weirdness

David Malone dwmalone at
Tue Jul 12 09:50:15 GMT 2005

> did the trick! now can someone remind me what inflight does? and could
> someone explain why increasing sendspace alone did not do the trick?
> (i had it at 64k, which got things better, but not sufficient).

TCP inflight limiting is supposed to guess the bandwidth-delay
product for a TCP connection and stop the window expanding much
above this. It's a pretty neat idea for DSL links that often have
huge buffers at the far end, where inflight limiting can prevent
delays to interactive traffic.

However, some of the guys I know that work on TCP dynamics reckon
that they can they can come up with situations where inflight
limiting will break. Unfortunately, I haven't had time to talk
this through with them. I guess you may have found one of those
situations ;-)


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