diff --git a/pkg/schedule/checker/checker_controller.go b/pkg/schedule/checker/checker_controller.go
index 17bf36cc92f..1c0492abd9b 100644
--- a/pkg/schedule/checker/checker_controller.go
+++ b/pkg/schedule/checker/checker_controller.go
@@ -282,6 +282,8 @@ func (c *Controller) CheckRegion(region *core.RegionInfo) []*operator.Operator {
 	}
 
 	if c.mergeChecker != nil {
+		operator.DebugIncOperatorCounter("op", opController.OperatorCount(operator.OpMerge))
+		operator.DebugIncOperatorCounter("limit", c.conf.GetMergeScheduleLimit())
 		allowed := opController.OperatorCount(operator.OpMerge) < c.conf.GetMergeScheduleLimit()
 		if !allowed {
 			operator.IncOperatorLimitCounter(c.mergeChecker.GetType(), operator.OpMerge)
diff --git a/pkg/schedule/operator/metrics.go b/pkg/schedule/operator/metrics.go
index 47a165500e9..ac3a9e3675d 100644
--- a/pkg/schedule/operator/metrics.go
+++ b/pkg/schedule/operator/metrics.go
@@ -80,6 +80,13 @@ var (
 			Help:      "Bucketed histogram of the operator region size.",
 			Buckets:   prometheus.ExponentialBuckets(1, 2, 20), // 1MB~1TB
 		}, []string{"type"})
+	debugOperatorCounter = prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Namespace: "pd",
+			Subsystem: "schedule",
+			Name:      "debug_operator_count",
+			Help:      "Counter of debug schedule operators.",
+		}, []string{"type"})
 )
 
 func init() {
@@ -90,9 +97,15 @@ func init() {
 	prometheus.MustRegister(operatorDuration)
 	prometheus.MustRegister(operatorSizeHist)
 	prometheus.MustRegister(storeLimitCostCounter)
+	prometheus.MustRegister(debugOperatorCounter)
 }
 
 // IncOperatorLimitCounter increases the counter of operator meeting limit.
 func IncOperatorLimitCounter(typ types.CheckerSchedulerType, kind OpKind) {
 	operatorLimitCounter.WithLabelValues(typ.String(), kind.String()).Inc()
 }
+
+// DebugIncOperatorCounter increases the counter of debug schedule operators.
+func DebugIncOperatorCounter(typ string, num uint64) {
+	debugOperatorCounter.WithLabelValues(typ).Set(float64(num))
+}