peer: wait a little before closing idle connections

It seems that it needs some time to set connections that just used
as idle.

etcd/peer.go

@@ -122,7 +122,7 @@ func (p *peer) post(d []byte) {
 	buf := bytes.NewBuffer(d)
 	resp, err := p.c.Post(p.url, "application/octet-stream", buf)
 	if err != nil {
-		log.Println("peer.post url=%s err=\"%v\"", p.url, err)
+		log.Printf("peer.post url=%s err=\"%v\"", p.url, err)
 		return
 	}
 	resp.Body.Close()

etcd/peer_hub.go

@@ -25,6 +25,7 @@ import (
 	"net/url"
 	"path"
 	"sync"
+	"time"
 
 	"github.com/coreos/etcd/raft"
 )
@@ -77,6 +78,9 @@ func (h *peerHub) stop() {
 	for _, p := range h.peers {
 		p.stop()
 	}
+	// http.Transport needs some time to put used connections
+	// into idle queues.
+	time.Sleep(time.Millisecond)
 	tr := h.c.Transport.(*http.Transport)
 	tr.CloseIdleConnections()
 }