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Signed-off-by: yisaer <disxiaofei@163.com>

server/statistics/hot_peer_cache.go

@@ -33,7 +33,6 @@ const (
 	// WriteReportInterval indicates the interval between write interval
 	WriteReportInterval = RegionHeartBeatReportInterval
 	// ReadReportInterval indicates the interval between read stats report
-	// TODO: use StoreHeartBeatReportInterval in future
 	ReadReportInterval = StoreHeartBeatReportInterval
 
 	rollingWindowsSize = 5
@@ -208,7 +207,7 @@ func (f *hotPeerCache) CheckPeerFlow(peer *core.PeerInfo, region *core.RegionInf
 		loads[i] = deltaLoads[i] / float64(interval)
 	}
 	justTransferLeader := f.justTransferLeader(region)
-	// transfer read leader or remove write peer
+	// remove peer
 	isExpired := f.isPeerExpired(peer, region)
 	oldItem := f.getOldHotPeerStat(region.GetID(), storeID)
 	if isExpired && oldItem != nil {
@@ -284,14 +283,7 @@ func (f *hotPeerCache) getOldHotPeerStat(regionID, storeID uint64) *HotPeerStat
 
 func (f *hotPeerCache) isPeerExpired(peer *core.PeerInfo, region *core.RegionInfo) bool {
 	storeID := peer.GetStoreID()
-	switch f.kind {
-	case WriteFlow:
-		return region.GetStorePeer(storeID) == nil
-	//TODO: make readFlow isPeerExpired condition as same as the writeFlow
-	case ReadFlow:
-		return region.GetLeader().GetStoreId() != storeID
-	}
-	return false
+	return region.GetStorePeer(storeID) == nil
 }
 
 func (f *hotPeerCache) calcHotThresholds(storeID uint64) []float64 {