HBASE-25329 Dump region hashes in logs for the regions that are stuck in transition for more than a configured amount of time

Author: Caroline Zhou

hbase-hadoop-compat/src/main/java/org/apache/hadoop/hbase/master/MetricsAssignmentManagerSource.java

@@ -40,7 +40,7 @@ public interface MetricsAssignmentManagerSource extends BaseSource {
   /**
    * Description
    */
-  String METRICS_DESCRIPTION = "Metrics about HBase master assingment manager.";
+  String METRICS_DESCRIPTION = "Metrics about HBase master assignment manager.";
 
   String RIT_COUNT_NAME = "ritCount";
   String RIT_COUNT_OVER_THRESHOLD_NAME = "ritCountOverThreshold";

hbase-server/src/main/java/org/apache/hadoop/hbase/master/AssignmentManager.java

@@ -3538,18 +3538,32 @@ public void updateRegionsInTransitionMetrics() {
     int totalRITs = 0;
     int totalRITsOverThreshold = 0;
     long oldestRITTime = 0;
+    Map<String, RegionState> ritsOverThreshold = null;
     int ritThreshold = this.server.getConfiguration().
       getInt(HConstants.METRICS_RIT_STUCK_WARNING_THRESHOLD, 60000);
     for (RegionState state: regionStates.getRegionsInTransition()) {
       totalRITs++;
       long ritTime = currentTime - state.getStamp();
       if (ritTime > ritThreshold) { // more than the threshold
         totalRITsOverThreshold++;
+        if (ritsOverThreshold == null) {
+          ritsOverThreshold = new HashMap<>();
+        }
+        ritsOverThreshold.put(state.getRegion().getEncodedName(), state);
       }
       if (oldestRITTime < ritTime) {
         oldestRITTime = ritTime;
       }
     }
+    if (LOG.isDebugEnabled() && ritsOverThreshold != null && !ritsOverThreshold.isEmpty()) {
+      StringBuilder sb = new StringBuilder();
+      for (Map.Entry<String, RegionState> regionName: ritsOverThreshold.entrySet()) {
+        sb.append(regionName).append(":")
+          .append(ritsOverThreshold.get(regionName).getState().name()).append("\n");
+      }
+      sb.delete(sb.length()-1, sb.length());
+      LOG.debug("RITs over threshold: " + sb.toString());
+    }
     if (this.metricsAssignmentManager != null) {
       this.metricsAssignmentManager.updateRITOldestAge(oldestRITTime);
       this.metricsAssignmentManager.updateRITCount(totalRITs);