tree 2c4ebd4148fb7324103990820ff4e34d71cc4d6f
parent cab90db24ac2e4ddbb9e7619f65bf5dc582783c0
author Victor Boivie <boivie@webrtc.org> 1621455762 +0200
committer WebRTC LUCI CQ <webrtc-scoped@luci-project-accounts.iam.gserviceaccount.com> 1621627709 +0000

dcsctp: Ensure RTO is always greater than RTT

The retransmission timeout (RTO) value is updated on every measured
RTT and is a function of the RTT value and its stability. In reality,
the RTT is never constant - it fluctuates, which makes the RTO become
much larger than the RTT. But for extremely stable RTTs, which we get
in simulations, the RTO value can become the same as the RTT, and that
makes expiration timers be scheduled to the RTT value, and will race
with packets that are expected to stop the expiration timer. And that
race should be avoided in simulations.

So ensuring that the RTO value is always greater, if only be a single
millisecond, will work fine in these simulations.

Bug: webrtc:12614
Change-Id: I30cf9c97e50449849ab35de52696c618d8498128
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/219680
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#34084}