[remove datanode] Do not disable the entire region group for one removing region (apache#14241)

* fix disabled

* fix disabled

Author: HxpSerein

iotdb-core/confignode/src/main/java/org/apache/iotdb/confignode/manager/load/cache/region/RegionGroupCache.java

@@ -110,29 +110,26 @@ private RegionGroupStatus caculateRegionGroupStatus(
       Map<Integer, RegionStatistics> regionStatisticsMap) {
     int unknownCount = 0;
     int readonlyCount = 0;
+    int removingCount = 0;
     for (RegionStatistics regionStatistics : regionStatisticsMap.values()) {
-      if (RegionStatus.Removing.equals(regionStatistics.getRegionStatus())) {
-        // The RegionGroup is considered as Disabled when
-        // at least one Region is in the ReadOnly or Removing status
-        return RegionGroupStatus.Disabled;
-      }
       unknownCount += RegionStatus.Unknown.equals(regionStatistics.getRegionStatus()) ? 1 : 0;
       readonlyCount += RegionStatus.ReadOnly.equals(regionStatistics.getRegionStatus()) ? 1 : 0;
+      removingCount += RegionStatus.Removing.equals(regionStatistics.getRegionStatus()) ? 1 : 0;
     }
 
-    if (unknownCount + readonlyCount == 0) {
+    if (unknownCount + readonlyCount + removingCount == 0) {
       // The RegionGroup is considered as Running only if
       // all Regions are in the Running status
       return RegionGroupStatus.Running;
     } else if (readonlyCount == 0) {
-      return unknownCount <= ((regionCacheMap.size() - 1) / 2)
+      return (unknownCount + removingCount) <= ((regionCacheMap.size() - 1) / 2)
           // The RegionGroup is considered as Available when the number of Unknown Regions is less
           // than half
           ? RegionGroupStatus.Available
           // Disabled otherwise
           : RegionGroupStatus.Disabled;
     } else {
-      return unknownCount + readonlyCount <= ((regionCacheMap.size() - 1) / 2)
+      return (unknownCount + readonlyCount + removingCount) <= ((regionCacheMap.size() - 1) / 2)
           // The RegionGroup is considered as Discouraged when the number of Unknown or ReadOnly
           // Regions is less
           // than half, and there are at least 1 ReadOnly Region

iotdb-core/confignode/src/main/java/org/apache/iotdb/confignode/manager/partition/RegionGroupStatus.java

@@ -24,24 +24,22 @@ public enum RegionGroupStatus {
   Running("Running", 1),
 
   /**
-   * All Regions in RegionGroup are in the Running or Unknown status, and the number of Regions in
-   * the Unknown status is less than half
+   * All Regions in RegionGroup are in the Running or Unknown or Removing status, and the number of
+   * Regions in the Unknown or Removing status is less than half
    */
   Available("Available", 2),
 
   /**
-   * All Regions in RegionGroup are in the Running, Unknown or ReadOnly status, and at least 1 node
-   * is in ReadOnly status, the number of Regions in the Unknown or ReadOnly status is less than
-   * half
+   * All Regions in RegionGroup are in the Running, Unknown or ReadOnly or Removing status, and at
+   * least 1 node is in ReadOnly status, the number of Regions in the Unknown or ReadOnly or
+   * Removing status is less than half
    */
   Discouraged("Discouraged", 3),
 
   /**
    * The following cases will lead to Disabled RegionGroup:
    *
-   * <p>1. There is a Region in Removing status
-   *
-   * <p>2. More than half of the Regions are in Unknown or ReadOnly status
+   * <p>1. More than half of the Regions are in Unknown or ReadOnly or Removing status
    */
   Disabled("Disabled", 4);
 

iotdb-core/confignode/src/test/java/org/apache/iotdb/confignode/manager/load/LoadManagerTest.java

@@ -188,7 +188,7 @@ public void testRegionGroupCache() throws InterruptedException {
     Assert.assertEquals(
         new Pair<>(
             new RegionGroupStatistics(RegionGroupStatus.Running, allRunningRegionStatisticsMap),
-            new RegionGroupStatistics(RegionGroupStatus.Disabled, oneRemovingRegionStatisticsMap)),
+            new RegionGroupStatistics(RegionGroupStatus.Available, oneRemovingRegionStatisticsMap)),
         differentRegionGroupStatisticsMap.get(regionGroupId));
     // Add and mark Region 3 as Adding
     int addDataNodeId = 3;
@@ -203,8 +203,8 @@ public void testRegionGroupCache() throws InterruptedException {
     oneAddingRegionStatisticsMap.put(addDataNodeId, new RegionStatistics(RegionStatus.Adding));
     Assert.assertEquals(
         new Pair<>(
-            new RegionGroupStatistics(RegionGroupStatus.Disabled, oneRemovingRegionStatisticsMap),
-            new RegionGroupStatistics(RegionGroupStatus.Disabled, oneAddingRegionStatisticsMap)),
+            new RegionGroupStatistics(RegionGroupStatus.Available, oneRemovingRegionStatisticsMap),
+            new RegionGroupStatistics(RegionGroupStatus.Available, oneAddingRegionStatisticsMap)),
         differentRegionGroupStatisticsMap.get(regionGroupId));
     // Both Region 0 and 3 can't be updated
     LOAD_CACHE.cacheRegionHeartbeatSample(
@@ -226,8 +226,8 @@ public void testRegionGroupCache() throws InterruptedException {
     oneRemovingRegionStatisticsMap.put(addDataNodeId, new RegionStatistics(RegionStatus.Running));
     Assert.assertEquals(
         new Pair<>(
-            new RegionGroupStatistics(RegionGroupStatus.Disabled, oneAddingRegionStatisticsMap),
-            new RegionGroupStatistics(RegionGroupStatus.Disabled, oneRemovingRegionStatisticsMap)),
+            new RegionGroupStatistics(RegionGroupStatus.Available, oneAddingRegionStatisticsMap),
+            new RegionGroupStatistics(RegionGroupStatus.Available, oneRemovingRegionStatisticsMap)),
         differentRegionGroupStatisticsMap.get(regionGroupId));
     // Removing process completed
     LOAD_MANAGER.removeRegionCache(regionGroupId, removeDataNodeId);
@@ -237,7 +237,7 @@ public void testRegionGroupCache() throws InterruptedException {
     allRunningRegionStatisticsMap.put(addDataNodeId, new RegionStatistics(RegionStatus.Running));
     Assert.assertEquals(
         new Pair<>(
-            new RegionGroupStatistics(RegionGroupStatus.Disabled, oneRemovingRegionStatisticsMap),
+            new RegionGroupStatistics(RegionGroupStatus.Available, oneRemovingRegionStatisticsMap),
             new RegionGroupStatistics(RegionGroupStatus.Running, allRunningRegionStatisticsMap)),
         differentRegionGroupStatisticsMap.get(regionGroupId));
   }

iotdb-core/confignode/src/test/java/org/apache/iotdb/confignode/manager/load/cache/RegionGroupCacheTest.java

@@ -123,7 +123,7 @@ public void getRegionGroupStatusTest() {
         2, new RegionHeartbeatSample(currentTime, RegionStatus.Removing));
     disabledRegionGroup2.updateCurrentStatistics();
     Assert.assertEquals(
-        RegionGroupStatus.Disabled,
+        RegionGroupStatus.Available,
         disabledRegionGroup2.getCurrentStatistics().getRegionGroupStatus());
   }
 }