[rack] Support running tcp_benchmarks with RACK.

PiperOrigin-RevId: 360491700

2 files changed, 13 insertions, 1 deletions

diff --git a/test/benchmarks/tcp/tcp_benchmark.sh b/test/benchmarks/tcp/tcp_benchmark.sh
index ef04b4ace..6a4f33b96 100755
--- a/test/benchmarks/tcp/tcp_benchmark.sh
+++ b/test/benchmarks/tcp/tcp_benchmark.sh
@@ -91,6 +91,9 @@ while [ $# -gt 0 ]; do
     --sack)
       netstack_opts="${netstack_opts} -sack"
       ;;
+    --rack)
+      netstack_opts="${netstack_opts} -rack"
+      ;;
     --cubic)
       netstack_opts="${netstack_opts} -cubic"
       ;;
@@ -150,8 +153,9 @@ while [ $# -gt 0 ]; do
       echo " --client              use netstack as the client"
       echo " --ideal               reset all network emulation"
       echo " --server              use netstack as the server"
-      echo " --mtu                 set the mtu (bytes)"      
+      echo " --mtu                 set the mtu (bytes)"
       echo " --sack                enable SACK support"
+      echo " --rack                enable RACK support"
       echo " --moderate-recv-buf   enable TCP receive buffer auto-tuning"
       echo " --cubic               enable CUBIC congestion control for Netstack"
       echo " --duration            set the test duration (s)"
diff --git a/test/benchmarks/tcp/tcp_proxy.go b/test/benchmarks/tcp/tcp_proxy.go
index 9fe60080c..780e4f7ae 100644
--- a/test/benchmarks/tcp/tcp_proxy.go
+++ b/test/benchmarks/tcp/tcp_proxy.go
@@ -56,6 +56,7 @@ var (
 	mask               = flag.Int("mask", 8, "mask size for address")
 	iface              = flag.String("iface", "", "network interface name to bind for netstack")
 	sack               = flag.Bool("sack", false, "enable SACK support for netstack")
+	rack               = flag.Bool("rack", false, "enable RACK in TCP")
 	moderateRecvBuf    = flag.Bool("moderate_recv_buf", false, "enable TCP Receive Buffer Auto-tuning")
 	cubic              = flag.Bool("cubic", false, "enable use of CUBIC congestion control for netstack")
 	gso                = flag.Int("gso", 0, "GSO maximum size")
@@ -232,6 +233,13 @@ func newNetstackImpl(mode string) (impl, error) {
 		}
 	}
 
+	if *rack {
+		opt := tcpip.TCPRecovery(tcpip.TCPRACKLossDetection)
+		if err := s.SetTransportProtocolOption(tcp.ProtocolNumber, &opt); err != nil {
+			return nil, fmt.Errorf("enabling RACK failed: %v", err)
+		}
+	}
+
 	// Enable Receive Buffer Auto-Tuning.
 	{
 		opt := tcpip.TCPModerateReceiveBufferOption(*moderateRecvBuf)