From a471681e285ba22ab1975e4c2ab92768156e4162 Mon Sep 17 00:00:00 2001 From: Jordan Whited Date: Tue, 25 Oct 2022 16:09:20 -0700 Subject: [PATCH] wgengine/netstack: enable TCP SACK (#6066) TCP selective acknowledgement can improve throughput by an order of magnitude in the presence of loss. Signed-off-by: Jordan Whited --- wgengine/netstack/netstack.go | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/wgengine/netstack/netstack.go b/wgengine/netstack/netstack.go index 374058a47..d1ed74fef 100644 --- a/wgengine/netstack/netstack.go +++ b/wgengine/netstack/netstack.go @@ -160,6 +160,11 @@ func Create(logf logger.Logf, tundev *tstun.Wrapper, e wgengine.Engine, mc *magi NetworkProtocols: []stack.NetworkProtocolFactory{ipv4.NewProtocol, ipv6.NewProtocol}, TransportProtocols: []stack.TransportProtocolFactory{tcp.NewProtocol, udp.NewProtocol, icmp.NewProtocol4, icmp.NewProtocol6}, }) + sackEnabledOpt := tcpip.TCPSACKEnabled(true) // TCP SACK is disabled by default + tcpipErr := ipstack.SetTransportProtocolOption(tcp.ProtocolNumber, &sackEnabledOpt) + if tcpipErr != nil { + return nil, fmt.Errorf("could not enable TCP SACK: %v", tcpipErr) + } linkEP := channel.New(512, mtu, "") if tcpipProblem := ipstack.CreateNIC(nicID, linkEP); tcpipProblem != nil { return nil, fmt.Errorf("could not create netstack NIC: %v", tcpipProblem)