Re: net.inet.tcp.inflight_enable

[Noritoshi Demizu <demizu@xxxxxxxxxxxxxx>]

>     Try increasing net.inet.tcp.inflight_stab from 20 to 40 and
>     see if that fixes ethe congestion window expansion problem.  I'm
>     not sure why the congestion window isn't expanding.

I tried it and put the results at the following page.

  http://www.demizu.org/~noritosi/memo/2005/0711/

I compared the throughput of BDP Limiting with the throughput of
congestion avoidance in my environment.  In my environment, I saw
that, if inflight_stab is lower than 50, the throughput of BDP
Limiting is lower than that of congestion avoidance, because
congestion window with BDP Limiting grows slower than that in
congestion avoidance.

As you know, in the congestion avoidance phase, congestion window is
increased one MSS per RTT.  With BDP Limiting, congestion window is
increased one MSS per several RTTs in my environment.

Regards,
Noritoshi Demizu