Clock jump heuristics might fail to cope with "suspend"
In proposals/324-rtt-congestion-control.txt
:
If the new RTT is either 5000 times larger than the EWMA
If the Tor client is suspended (for example, because a laptop is suspended), it might experience long RTT estimates, if the monotonic timer advances during suspend (which some will do). Supposing an RTT of 1s, many plausible suspension durations might be much shorter than the 5000 figure. I think the result would be an RTT estimate that would be badly skewed, upwards.
AFAICT from the rest of the congestion control docs, this would result in sending too much data.
I feel I may well be missing something so please forgive me if I have the wrong end of the stick(s).