Re: debugging TCP stalls on high-speed wifi

On Thu, 2019-12-12 at 13:50 -0800, Eric Dumazet wrote:

I presume you could hack TCP to no longer care about bufferbloat and you'll
probably match Windows 'performance' on a single flow and a lossless network.

Ie always send ~64KB TSO packets and fill the queues, inflating RTT.

Then, in presence of losses, you get a problem because the retransmit packets
can only be sent _after_ the huge queue that has been put on the sender.

Sure, I'll do it as an experiment. Got any suggestions on how to do
that?

I tried to decrease sk_pacing_shift even further with no effect, I've
also tried many more TCP streams with no effect.

I don't even care about a single flow that much, honestly. The default
test is like 10 or 20 flows anyway.

If only TCP could predict the future ;)

:)

johannes