Merge pull request #3052 from prometheus/connleak

Kill idle connections after 5 minutes

retrieval/scrape.go

@@ -420,6 +420,7 @@ func (s *targetScraper) scrape(ctx context.Context, w io.Writer) error {
 
 		s.req = req
 	}
+
 	resp, err := ctxhttp.Do(ctx, s.client, s.req)
 	if err != nil {
 		return err

util/httputil/client.go

@@ -47,6 +47,9 @@ func NewClientFromConfig(cfg config.HTTPClientConfig) (*http.Client, error) {
 		DisableKeepAlives:  false,
 		TLSClientConfig:    tlsConfig,
 		DisableCompression: true,
+		// 5 minutes is typically above the maximum sane scrape interval. So we can
+		// use keepalive for all configurations.
+		IdleConnTimeout: 5 * time.Minute,
 	}
 
 	// If a bearer token is provided, create a round tripper that will set the

web/web.go

@@ -346,8 +346,16 @@ func (h *Handler) Run(ctx context.Context) error {
 		ReadTimeout: h.options.ReadTimeout,
 	}
 
-	go httpSrv.Serve(httpl)
+	go func() {
-	go grpcSrv.Serve(grpcl)
+		if err := httpSrv.Serve(httpl); err != nil {
+			log.With("err", err).Warnf("error serving HTTP")
+		}
+	}()
+	go func() {
+		if err := grpcSrv.Serve(grpcl); err != nil {
+			log.With("err", err).Warnf("error serving HTTP")
+		}
+	}()
 
 	return m.Serve()
 }