tools: use metrics to record statistics (#5673)

ref #5468

Signed-off-by: Ryan Leung <rleungx@gmail.com>

Co-authored-by: Ti Chi Robot <ti-community-prow-bot@tidb.io>

tools/pd-simulator/main.go

@@ -206,7 +206,6 @@ EXIT:
 	}
 
 	fmt.Printf("%s [%s] total iteration: %d, time cost: %v\n", simResult, simCase, driver.TickCount(), time.Since(start))
-	driver.PrintStatistics()
 	if analysis.GetTransferCounter().IsValid {
 		analysis.GetTransferCounter().PrintResult()
 	}

tools/pd-simulator/simulator/drive.go

@@ -163,11 +163,6 @@ func (d *Driver) Check() bool {
 	return d.simCase.Checker(d.raftEngine.regionsInfo, stats)
 }
 
-// PrintStatistics prints the statistics of the scheduler.
-func (d *Driver) PrintStatistics() {
-	d.raftEngine.schedulerStats.PrintStatistics()
-}
-
 // Start starts all nodes.
 func (d *Driver) Start() error {
 	for _, n := range d.conn.Nodes {

tools/pd-simulator/simulator/metrics.go

@@ -11,8 +11,26 @@ var (
 			Help:      "Bucketed histogram of processing time (s) of handled snap requests.",
 			Buckets:   prometheus.ExponentialBuckets(0.0005, 2, 20),
 		}, []string{"store", "type"})
+
+	schedulingCounter = prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Namespace: "pd",
+			Subsystem: "schedule",
+			Name:      "scheduling_count",
+			Help:      "Counter of region scheduling",
+		}, []string{"type"})
+
+	snapshotCounter = prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Namespace: "pd",
+			Subsystem: "schedule",
+			Name:      "snapshot_count",
+			Help:      "Counter of region snapshot",
+		}, []string{"store", "type"})
 )
 
 func init() {
 	prometheus.MustRegister(snapDuration)
+	prometheus.MustRegister(schedulingCounter)
+	prometheus.MustRegister(snapshotCounter)
 }

tools/pd-simulator/simulator/raft.go

@@ -32,7 +32,6 @@ type RaftEngine struct {
 	regionsInfo       *core.RegionsInfo
 	conn              *Connection
 	regionChange      map[uint64][]uint64
-	schedulerStats    *schedulerStatistics
 	regionSplitSize   int64
 	regionSplitKeys   int64
 	storeConfig       *SimConfig
@@ -45,7 +44,6 @@ func NewRaftEngine(conf *cases.Case, conn *Connection, storeConfig *SimConfig) *
 		regionsInfo:     core.NewRegionsInfo(),
 		conn:            conn,
 		regionChange:    make(map[uint64][]uint64),
-		schedulerStats:  newSchedulerStatistics(),
 		regionSplitSize: conf.RegionSplitSize,
 		regionSplitKeys: conf.RegionSplitKeys,
 		storeConfig:     storeConfig,