You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: metrics.go
    path of file: ./repos/ziti/router/xgress
    
    the code of the file until where you have to start completion: package xgress

import (
	"github.com/openziti/metrics"
	"sync/atomic"
)

var ackTxMeter metrics.Meter
var ackRxMeter metrics.Meter
var droppedPayloadsMeter metrics.Meter
var retransmissions metrics.Meter
var retransmissionFailures metrics.Meter

var ackFailures metrics.Meter
var payloadWriteTimer metrics.Timer
var duplicateAcksMeter metrics.Meter

var buffersBlockedByLocalWindow int64
var buffersBlockedByRemoteWindow int64
var outstandingPayloads int64
var outstandingPayloadBytes int64

func InitMetrics(registry metrics.UsageRegistry) {
	droppedPayloadsMeter = registry.Meter("xgress.dropped_payloads")
	retransmissions = registry.Meter("xgress.retransmissions")
	retransmissionFailures = registry.Meter("xgress.retransmission_failures")
	ackRxMeter = registry.Meter("xgress.rx.acks")
	ackTxMeter = registry.Meter("xgress.tx.acks")
	ackFailures = registry.Meter("xgress.ack_failures")
	payloadW
    
func InitMetrics(registry metrics.UsageRegistry) {
	droppedPayloadsMeter = registry.Meter("xgress.dropped_payloads")
	retransmissions = registry.Meter("xgress.retransmissions")
	retransmissionFailures = registry.Meter("xgress.retransmission_failures")
	ackRxMeter = registry.Meter("xgress.rx.acks")
	ackTxMeter = registry.Meter("xgress.tx.acks")
	ackFailures = registry.Meter("xgress.ack_failures")
	payloadWriteTimer = registry.Timer("xgress.tx_write_time")
	duplicateAcksMeter = registry.Meter("xgress.ack_duplicates")

	registry.FuncGauge("xgress.blocked_by_local_window", func() int64 {
		return atomic.LoadInt64(&buffersBlockedByLocalWindow)
	})

	registry.FuncGauge("xgress.blocked_by_remote_window", func() int64 {
		return atomic.LoadInt64(&buffersBlockedByRemoteWindow)
	})

	registry.FuncGauge("xgress.tx_unacked_payloads", func() int64 {
		return atomic.LoadInt64(&outstandingPayloads)
	})

	registry.FuncGauge("xgress.tx_unacked_payload_bytes", func() int64 {
		return atomic.LoadInt64(&outstandingPayloadBytes)
	})
}