TT_KEEP reset

Randall Stewart rrs at
Wed Feb 17 15:36:37 UTC 2021

I have not followed all the TCPM discussion but how
would tt_rexmt be active if you are in keep-alive?

Keep alive can only go active if there is nothing to send
and nothing outstanding.. so why would tt_rexmt be ever active?

For persists I am not so sure. Normally you go into persists
when you have data to send and the rwnd of the peer has closed.
Again if that’s true i.e. you have data for the peer, then
you would never be in KEEP.. though I could see where the peer
ack’d the last byte and closed its window to zero… in this
case you *might* want both but I need to think about that case its
a bit strange ;-)


> On Feb 16, 2021, at 8:09 AM, Scheffenegger, Richard <Richard.Scheffenegger at> wrote:
> Hi,
> From the discussion @tcpm, around 793bis - shall we add conditionals to reset the TT_KEEP timer, in case a tt_persist or tt_rexmt are active?
> Richard Scheffenegger
> _______________________________________________
> freebsd-transport at mailing list
> To unsubscribe, send any mail to "freebsd-transport-unsubscribe at"

Randall Stewart
rrs at

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