fix: optimize for ping result expire

selector.go

@@ -214,7 +214,7 @@ type FastestFilter struct {
 
 	pinger        *net.Dialer
 	pingResult    map[int]int
-	pingResultTTL map[int]int
+	pingResultTTL map[int]int64
 
 	topCount int
 }
@@ -227,7 +227,7 @@ func NewFastestFilter(pingTimeOut int, topCount int) *FastestFilter {
 		mu:            sync.Mutex{},
 		pinger:        &net.Dialer{Timeout: time.Millisecond * time.Duration(pingTimeOut)},
 		pingResult:    make(map[int]int, 0),
-		pingResultTTL: make(map[int]int, 0),
+		pingResultTTL: make(map[int]int64, 0),
 		topCount:      topCount,
 	}
 }
@@ -240,19 +240,22 @@ func (f *FastestFilter) Filter(nodes []Node) []Node {
 
 	// get latency with ttl cache
 	now := time.Now().Unix()
+	r := rand.New(rand.NewSource(time.Now().UnixNano()))
+
 	var getNodeLatency = func(node Node) int {
-		if now-int64(f.pingResultTTL[node.ID]) > 60*5 {
+		if f.pingResultTTL[node.ID] < now {
 			f.mu.Lock()
-			f.pingResultTTL[node.ID] = int(now)
+			f.pingResultTTL[node.ID] = now + 5 // tmp
 			defer f.mu.Unlock()
 
 			// get latency
 			go func(node Node) {
 				latency := f.doTcpPing(node.Addr)
+				ttl := 300 - int64(60*r.Float64())
 
 				f.mu.Lock()
 				f.pingResult[node.ID] = latency
-				f.pingResultTTL[node.ID] = int(time.Now().Unix())
+				f.pingResultTTL[node.ID] = ttl
 				defer f.mu.Unlock()
 			}(node)
 		}