From: Florin Coras <fcoras@cisco.com>
Date: Fri, 22 Mar 2024 23:12:53 +0000 (-0700)
Subject: tcp: avoid fr segments less than mss if possible
X-Git-Url: https://gerrit.fd.io/r/gitweb?p=vpp.git;a=commitdiff_plain;h=e8ea6be8dfb626b5bb4ff3355ce8037724ce1d83

tcp: avoid fr segments less than mss if possible

Type: improvement

Change-Id: I958e059384db3c13a29f64be96877f57617bbae2
Signed-off-by: Florin Coras <fcoras@cisco.com>
---

diff --git a/src/vnet/tcp/tcp_output.c b/src/vnet/tcp/tcp_output.c
index e232ed43b69..78148cd5695 100644
--- a/src/vnet/tcp/tcp_output.c
+++ b/src/vnet/tcp/tcp_output.c
@@ -1810,7 +1810,11 @@ tcp_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
 	  break;
 	}
 
-      max_bytes = clib_min (hole->end - sb->high_rxt, snd_space);
+      max_bytes = hole->end - sb->high_rxt;
+      /* Avoid retransmitting segment less than mss if possible */
+      if (snd_space < tc->snd_mss && max_bytes > snd_space)
+	break;
+      max_bytes = clib_min (max_bytes, snd_space);
       max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes;
       if (max_bytes == 0)
 	break;