[GitHub] [hbase] ndimiduk commented on a change in pull request #2014: HBASE-24673 TransitionRegionStateProcedure of non-meta regions should…

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ndimiduk commented on a change in pull request #2014:
URL: https://github.com/apache/hbase/pull/2014#discussion_r492290457



##########
File path: hbase-server/src/main/java/org/apache/hadoop/hbase/master/assignment/TransitRegionStateProcedure.java
##########
@@ -200,14 +200,21 @@ private void queueAssign(MasterProcedureEnv env, RegionStateNode regionNode)
     }
   }
 
-  private void openRegion(MasterProcedureEnv env, RegionStateNode regionNode) throws IOException {
+  private void openRegion(MasterProcedureEnv env, RegionStateNode regionNode)
+    throws IOException, ProcedureSuspendedException {
     ServerName loc = regionNode.getRegionLocation();
     if (loc == null) {
       LOG.warn("No location specified for {}, jump back to state {} to get one", getRegion(),
         RegionStateTransitionState.REGION_STATE_TRANSITION_GET_ASSIGN_CANDIDATE);
       setNextState(RegionStateTransitionState.REGION_STATE_TRANSITION_GET_ASSIGN_CANDIDATE);
       return;
     }
+    final boolean isMeta = regionNode.getRegionInfo().isMetaRegion();
+    final boolean isMetaAvailable = !env.getAssignmentManager().isMetaRegionInTransition();
+    if (!isMeta && !isMetaAvailable) {
+      // meta is not assigned yet, so yield
+      throw new ProcedureSuspendedException();

Review comment:
       Update the patch to use existing mechanisms in `HMaster` for deciding if meta is assigned and the server hosting it is online.
   
   > So in general, we should have a way to deal with meta update failure(maybe just a retry at procedure level?)and have a smaller timeout on updaing meta operation.
   
   Looks like we deal with meta update failure by aborting the master, at least as of [ee3e2b974b](https://github.com/apache/hbase/blob/ee3e2b974ba0653e0c79d45d6e15fd30b4557167/hbase-server/src/main/java/org/apache/hadoop/hbase/master/assignment/RegionStateStore.java#L221):
   
   ```
     private void updateRegionLocation(RegionInfo regionInfo, State state, Put put)
         throws IOException {
       try (Table table = master.getConnection().getTable(TableName.META_TABLE_NAME)) {
         table.put(put);
       } catch (IOException e) {
         // TODO: Revist!!!! Means that if a server is loaded, then we will abort our host!
         // In tests we abort the Master!
         String msg = String.format("FAILED persisting region=%s state=%s",
           regionInfo.getShortNameToLog(), state);
         LOG.error(msg, e);
         master.abort(msg, e);
         throw e;
       }
     }
   ```




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