diff --git a/fe/fe-core/src/main/java/org/apache/doris/catalog/TabletInvertedIndex.java b/fe/fe-core/src/main/java/org/apache/doris/catalog/TabletInvertedIndex.java
index 0362205dbdef94..a1faada3fea669 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/catalog/TabletInvertedIndex.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/catalog/TabletInvertedIndex.java
@@ -718,6 +718,20 @@ public List<Replica> getReplicasByTabletId(long tabletId) {
         }
     }
 
+    public Long getTabletSizeByBackendId(long backendId) {
+        Long ret = 0L;
+        long stamp = readLock();
+        try {
+            Map<Long, Replica> replicaMetaWithBackend = backingReplicaMetaTable.row(backendId);
+            if (replicaMetaWithBackend != null) {
+                ret += replicaMetaWithBackend.size();
+            }
+        } finally {
+            readUnlock(stamp);
+        }
+        return ret;
+    }
+
     public List<Long> getTabletIdsByBackendId(long backendId) {
         List<Long> tabletIds = Lists.newArrayList();
         long stamp = readLock();
diff --git a/fe/fe-core/src/main/java/org/apache/doris/system/SystemInfoService.java b/fe/fe-core/src/main/java/org/apache/doris/system/SystemInfoService.java
index 8df709c8ace14a..316a53b1ce0139 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/system/SystemInfoService.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/system/SystemInfoService.java
@@ -482,7 +482,7 @@ public int getStartPosOfRoundRobin(Tag tag, TStorageMedium storageMedium, boolea
         long minBeTabletsNum = Long.MAX_VALUE;
         int minIndex = -1;
         for (int i = 0; i < beIds.size(); ++i) {
-            long tabletsNum = Env.getCurrentInvertedIndex().getTabletIdsByBackendId(beIds.get(i)).size();
+            long tabletsNum = Env.getCurrentInvertedIndex().getTabletSizeByBackendId(beIds.get(i));
             if (tabletsNum < minBeTabletsNum) {
                 minBeTabletsNum = tabletsNum;
                 minIndex = i;