diff --git a/runtest.sh b/runtest.sh
index 73cfbc6..5ead78d 100755
--- a/runtest.sh
+++ b/runtest.sh
@@ -111,7 +111,7 @@ run_iperf() {
   log "Running iperf3 $mode $direction to $target..."
   SECONDS=0
   if ! timeout "${timeout_duration}s" iperf3 "${args[@]}" >"$tmp_json" 2>"$tmp_err"; then
-    warn "iperf3 $mode $direction to $target failed or timed out"
+    warn "iperf3 $mode $direction to $target failed or timed out after $SECONDS"
     echo "0"
     return
   fi