使用trace进行排查网络瓶颈

func NewHTTPTraceLogger(ctx context.Context, fileUrl string, fragmentID, attempt int) context.Context {
	traceStart := time.Now()
	var dnsStart, connectStart, tlsStart, gotConnTime time.Time

	trace := &httptrace.ClientTrace{
		DNSStart: func(info httptrace.DNSStartInfo) {
			dnsStart = time.Now()
		},
		DNSDone: func(info httptrace.DNSDoneInfo) {
			g.Log().Infof(ctx, "[trace] fileUrl=%s fragment=%d attempt=%d DNSDone: %+v cost=%v",
				fileUrl, fragmentID, attempt, info, time.Since(dnsStart))
		},
		ConnectStart: func(network, addr string) {
			connectStart = time.Now()
		},
		ConnectDone: func(network, addr string, err error) {
			g.Log().Infof(ctx, "[trace] fileUrl=%s fragment=%d attempt=%d ConnectDone: %s %s err=%v cost=%v",
				fileUrl, fragmentID, attempt, network, addr, err, time.Since(connectStart))
		},
		TLSHandshakeStart: func() {
			tlsStart = time.Now()
		},
		TLSHandshakeDone: func(cs tls.ConnectionState, err error) {
			g.Log().Infof(ctx, "[trace] fileUrl=%s fragment=%d attempt=%d TLSHandshakeDone err=%v cost=%v",
				fileUrl, fragmentID, attempt, err, time.Since(tlsStart))
		},
		GotConn: func(connInfo httptrace.GotConnInfo) {
			gotConnTime = time.Now()
			total := time.Since(traceStart)
			g.Log().Infof(ctx, "[trace] fileUrl=%s fragment=%d attempt=%d GotConn reused=%v idleTime=%v total=%v",
				fileUrl, fragmentID, attempt, connInfo.Reused, connInfo.IdleTime, total)
		},
		GotFirstResponseByte: func() {
			ttfb := time.Since(gotConnTime)
			g.Log().Infof(ctx, "[trace] fileUrl=%s fragment=%d attempt=%d GotFirstResponseByte TTFB=%v",
				fileUrl, fragmentID, attempt, ttfb)
		},
	}

	return httptrace.WithClientTrace(ctx, trace)
}

　　使用：

func NewHTTPTraceLogger(ctx context.Context, fileUrl string, fragmentID, attempt int) context.Context {
	traceStart := time.Now()
	var dnsStart, connectStart, tlsStart, gotConnTime time.Time

	trace := &httptrace.ClientTrace{
		DNSStart: func(info httptrace.DNSStartInfo) {
			dnsStart = time.Now()
		},
		DNSDone: func(info httptrace.DNSDoneInfo) {
			g.Log().Infof(ctx, "[trace] fileUrl=%s fragment=%d attempt=%d DNSDone: %+v cost=%v",
				fileUrl, fragmentID, attempt, info, time.Since(dnsStart))
		},
		ConnectStart: func(network, addr string) {
			connectStart = time.Now()
		},
		ConnectDone: func(network, addr string, err error) {
			g.Log().Infof(ctx, "[trace] fileUrl=%s fragment=%d attempt=%d ConnectDone: %s %s err=%v cost=%v",
				fileUrl, fragmentID, attempt, network, addr, err, time.Since(connectStart))
		},
		TLSHandshakeStart: func() {
			tlsStart = time.Now()
		},
		TLSHandshakeDone: func(cs tls.ConnectionState, err error) {
			g.Log().Infof(ctx, "[trace] fileUrl=%s fragment=%d attempt=%d TLSHandshakeDone err=%v cost=%v",
				fileUrl, fragmentID, attempt, err, time.Since(tlsStart))
		},
		GotConn: func(connInfo httptrace.GotConnInfo) {
			gotConnTime = time.Now()
			total := time.Since(traceStart)
			g.Log().Infof(ctx, "[trace] fileUrl=%s fragment=%d attempt=%d GotConn reused=%v idleTime=%v total=%v",
				fileUrl, fragmentID, attempt, connInfo.Reused, connInfo.IdleTime, total)
		},
		GotFirstResponseByte: func() {
			ttfb := time.Since(gotConnTime)
			g.Log().Infof(ctx, "[trace] fileUrl=%s fragment=%d attempt=%d GotFirstResponseByte TTFB=%v",
				fileUrl, fragmentID, attempt, ttfb)
		},
	}

	return httptrace.WithClientTrace(ctx, trace)
}