metric: fix too large block handle delay metrics; (bnb-chain#3102)

Author: galaio

eth/backend.go

@@ -79,6 +79,10 @@ const (
 	ChainData        = "chaindata"
 )
 
+const (
+	MaxBlockHandleDelayMs = 3000 // max delay for block handles, max 3000 ms
+)
+
 var (
 	sendBlockTimer        = metrics.NewRegisteredTimer("chain/delay/block/send", nil)
 	recvBlockTimer        = metrics.NewRegisteredTimer("chain/delay/block/recv", nil)
@@ -901,32 +905,39 @@ func (s *Ethereum) reportRecentBlocksLoop() {
 			records["BlockTime"] = common.FormatMilliTime(blockMsTime)
 			metrics.GetOrRegisterLabel("report-blocks", nil).Mark(records)
 
-			if sendBlockTime > blockMsTime {
+			if validTimeMetric(blockMsTime, sendBlockTime) {
 				sendBlockTimer.Update(time.Duration(sendBlockTime - blockMsTime))
 			}
-			if recvNewBlockTime > blockMsTime {
+			if validTimeMetric(blockMsTime, recvNewBlockTime) {
 				recvBlockTimer.Update(time.Duration(recvNewBlockTime - blockMsTime))
 			}
-			if startImportBlockTime > blockMsTime {
+			if validTimeMetric(blockMsTime, startImportBlockTime) {
 				startInsertBlockTimer.Update(time.Duration(startImportBlockTime - blockMsTime))
 			}
-			if sendVoteTime > blockMsTime {
+			if validTimeMetric(blockMsTime, sendVoteTime) {
 				sendVoteTimer.Update(time.Duration(sendVoteTime - blockMsTime))
 			}
-			if firstVoteTime > blockMsTime {
+			if validTimeMetric(blockMsTime, firstVoteTime) {
 				firstVoteTimer.Update(time.Duration(firstVoteTime - blockMsTime))
 			}
-			if recvMajorityTime > blockMsTime {
+			if validTimeMetric(blockMsTime, recvMajorityTime) {
 				majorityVoteTimer.Update(time.Duration(recvMajorityTime - blockMsTime))
 			}
-			if importedBlockTime > blockMsTime {
+			if validTimeMetric(blockMsTime, importedBlockTime) {
 				importedBlockTimer.Update(time.Duration(importedBlockTime - blockMsTime))
 			}
-			if startMiningTime < blockMsTime {
+			if validTimeMetric(startMiningTime, blockMsTime) {
 				startMiningTimer.Update(time.Duration(blockMsTime - startMiningTime))
 			}
 		case <-s.stopCh:
 			return
 		}
 	}
 }
+
+func validTimeMetric(startMs, endMs int64) bool {
+	if startMs >= endMs {
+		return false
+	}
+	return endMs-startMs <= MaxBlockHandleDelayMs
+}