=== LACP retransmit cause investigation (sender) ===
Host: pfv-tsys7   Role: sender
Date: 2026-07-27T13:57:55Z
Bond: bond0

--- bond0 hash + driver ---
Bonding Mode: IEEE 802.3ad Dynamic link aggregation
Transmit Hash Policy: layer3+4 (1)
	Number of ports: 2
	Partner Mac Address: 00:13:72:46:95:e4
  nic1     driver=tg3                  speed=1000   current RX ring=2047
  nic2     driver=tg3                  speed=1000   current RX ring=2047


--- iperf3 summary ---
[SUM]   0.00-12.00  sec  2.37 GBytes  1.69 Gbits/sec  69187             sender
[SUM]   0.00-12.00  sec  2.36 GBytes  1.69 Gbits/sec                  receiver

--- TCP SNMP deltas (/proc/net/snmp) ---
  ActiveOpens                   80334 ->        80371  delta=37
  EstabResets                      14 ->           21  delta=7
  InSegs                      3887134 ->      4130320  delta=243186
  OutSegs                    10112473 ->     12172271  delta=2059798
  RetransSegs                  259532 ->       340946  delta=81414

--- softnet_stat deltas (look for non-zero dropped_delta/squeezed_delta) ---

--- NIC counter deltas (only non-zero) ---
  [nic1]   sysfs multicast                       16340 ->        16342  delta=2
  [nic2]   sysfs multicast                       38862 ->        38872  delta=10

--- raw iperf3 tail (last 12 lines) ---
[ 13]   0.00-12.00  sec  87.9 MBytes  61.4 Mbits/sec  7050            sender
[ 13]   0.00-12.00  sec  87.2 MBytes  61.0 Mbits/sec                  receiver
[ 15]   0.00-12.00  sec   538 MBytes   376 Mbits/sec    0            sender
[ 15]   0.00-12.00  sec   538 MBytes   376 Mbits/sec                  receiver
[ 17]   0.00-12.00  sec   378 MBytes   264 Mbits/sec  19608            sender
[ 17]   0.00-12.00  sec   378 MBytes   264 Mbits/sec                  receiver
[ 19]   0.00-12.00  sec   327 MBytes   229 Mbits/sec  12049            sender
[ 19]   0.00-12.00  sec   327 MBytes   228 Mbits/sec                  receiver
[SUM]   0.00-12.00  sec  2.37 GBytes  1.69 Gbits/sec  69187             sender
[SUM]   0.00-12.00  sec  2.36 GBytes  1.69 Gbits/sec                  receiver

iperf Done.

===================================================================
 HOW TO READ THIS
===================================================================
 - If NIC rx_dropped / rx_missed_errors / rx_fifo_errors climbed:
     -> ring buffers too small. Fix: ethtool -G $IF rx 4096 (or max).
 - If softnet_stat 'dropped' or 'squeezed' climbed on any CPU:
     -> softirq starvation. Fix: increase net.core.netdev_budget,
        check IRQ affinity, consider RPS.
 - If NEITHER of the above climbed but TCP RetransSegs did:
     -> the retransmits are LACP reordering (out-of-order segments
        triggering fast retransmit), NOT packet loss. NOT fixable.
===================================================================
