From 3f71b8ba1255e83c5702d4769230d5007c828a3d Mon Sep 17 00:00:00 2001 From: Pietro De Domenico Date: Thu, 12 Nov 2026 16:56:44 +0100 Subject: [PATCH 2/2] tcp: Log additions to low RTT table Entries in the low RTT table never expire, and a wrong one makes every connection with that peer stall, but nothing shows that a peer was added: the only visible symptom is retransmissions inside the namespace. Print a debug message with the address and the measured minimum RTT whenever a peer is added. Co-Authored-By: Claude Opus 5.5 Signed-off-by: Pietro De Domenico --- tcp.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/tcp.c b/tcp.c index d88ebd4..4aef854 100644 --- a/tcp.c +++ b/tcp.c @@ -755,6 +755,7 @@ static void tcp_rtt_dst_check(const struct tcp_tap_conn *conn, const struct tcp_info_linux *tinfo) { const struct flowside *tapside = TAPFLOW(conn); + char buf[INANY_ADDRSTRLEN]; int i, hole = -1; if (!min_rtt_cap || @@ -775,6 +776,10 @@ static void tcp_rtt_dst_check(const struct tcp_tap_conn *conn, if (hole == -1) return; + flow_dbg(conn, "Adding %s to low RTT table, minimum RTT: %u us", + inany_ntop(&tapside->oaddr, buf, sizeof(buf)), + tinfo->tcpi_min_rtt); + low_rtt_dst[hole++] = tapside->oaddr; if (hole == LOW_RTT_TABLE_SIZE) hole = 0; -- 2.56.0