From 3c5bb78126e51a15a9a060df527e4d461bbbeec3 Mon Sep 17 00:00:00 2001
From: Johannes Truschnigg <johannes@truschnigg.info>
Date: Sun, 20 Mar 2022 10:31:44 +0100
Subject: [PATCH] Make low-latency mode step downwards more gracefully

---
 __lagdetect.awk | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/__lagdetect.awk b/__lagdetect.awk
index c97a8fc..5ba3751 100644
--- a/__lagdetect.awk
+++ b/__lagdetect.awk
@@ -254,8 +254,9 @@ function adjust_sqm(peername, latency) {
   if (last2avg > thresh_fudged) {
     if (latency > ping_prev[peername] && latency > ping_pprev[peername]) {
       if (prefer_high_bw == 0) {
-          bw_step_rx_next = 0
-          bw_step_rx_cur = 0
+          _low_step = max(0, int((bw_step_rx_cur / 2) - 2))
+          bw_step_rx_next = _low_step
+          bw_step_rx_cur = _low_step
           print "--- " ts " low-latency mode enforces step " bw_step_rx_next " := " STEPS_RX[bw_step_rx_next] "Kbps rx=" rx_rate " tx=" tx_rate
           set_bw(IFACE_RX, STEPS_RX[bw_step_rx_next])
 	  return
@@ -350,6 +351,14 @@ function set_bw(dev, kbit) {
 }
 
 
+function max (a, b) {
+  if (a > b) {
+    return a
+  }
+  return b
+}
+
+
 END {
   print "# " ts " BYE"
   # Usually not reached.
-- 
2.39.5