dbug: num-live counts number of packets in flight
'rtt'^(numb (div rtt ~s1))
'rttvar'^(numb (div rttvar ~s1))
'ssthresh'^(numb ssthresh)
- 'num-live'^(numb num-live)
+ 'num-live'^(numb ~(wyt by live))
'cwnd'^(numb cwnd)
'counter'^(numb counter)
==
