diff options
| -rw-r--r-- | pkg/sentry/socket/netstack/netstack.go | 1 | ||||
| -rw-r--r-- | pkg/tcpip/tcpip.go | 4 | ||||
| -rw-r--r-- | pkg/tcpip/transport/tcp/snd.go | 7 |
3 files changed, 12 insertions, 0 deletions
diff --git a/pkg/sentry/socket/netstack/netstack.go b/pkg/sentry/socket/netstack/netstack.go index 0f8cbe7e2..9b844b0c0 100644 --- a/pkg/sentry/socket/netstack/netstack.go +++ b/pkg/sentry/socket/netstack/netstack.go @@ -274,6 +274,7 @@ var Metrics = tcpip.Stats{ Timeouts: mustCreateMetric("/netstack/tcp/timeouts", "Number of times RTO expired."), ChecksumErrors: mustCreateMetric("/netstack/tcp/checksum_errors", "Number of segments dropped due to bad checksums."), FailedPortReservations: mustCreateMetric("/netstack/tcp/failed_port_reservations", "Number of time TCP failed to reserve a port."), + SegmentsAckedWithDSACK: mustCreateMetric("/netstack/tcp/segments_acked_with_dsack", "Number of segments for which DSACK was received."), }, UDP: tcpip.UDPStats{ PacketsReceived: mustCreateMetric("/netstack/udp/packets_received", "Number of UDP datagrams received via HandlePacket."), diff --git a/pkg/tcpip/tcpip.go b/pkg/tcpip/tcpip.go index 8f2658f64..55683b4fb 100644 --- a/pkg/tcpip/tcpip.go +++ b/pkg/tcpip/tcpip.go @@ -1845,6 +1845,10 @@ type TCPStats struct { // FailedPortReservations is the number of times TCP failed to reserve // a port. FailedPortReservations *StatCounter + + // SegmentsAckedWithDSACK is the number of segments acknowledged with + // DSACK. + SegmentsAckedWithDSACK *StatCounter } // UDPStats collects UDP-specific stats. diff --git a/pkg/tcpip/transport/tcp/snd.go b/pkg/tcpip/transport/tcp/snd.go index 72d58dcff..92a66f17e 100644 --- a/pkg/tcpip/transport/tcp/snd.go +++ b/pkg/tcpip/transport/tcp/snd.go @@ -1154,6 +1154,13 @@ func (s *sender) walkSACK(rcvdSeg *segment) { idx := 0 n := len(rcvdSeg.parsedOptions.SACKBlocks) if checkDSACK(rcvdSeg) { + dsackBlock := rcvdSeg.parsedOptions.SACKBlocks[0] + numDSACK := uint64(dsackBlock.End-dsackBlock.Start) / uint64(s.MaxPayloadSize) + // numDSACK can be zero when DSACK is sent for subsegments. + if numDSACK < 1 { + numDSACK = 1 + } + s.ep.stack.Stats().TCP.SegmentsAckedWithDSACK.IncrementBy(numDSACK) s.rc.setDSACKSeen(true) idx = 1 n-- |