From 453de3a66cc8eb91b0c6ed666f7aef0b54358677 Mon Sep 17 00:00:00 2001
From: Zhihong Yu <tedyu@apache.org>
Date: Sat, 31 Dec 2011 15:43:19 +0000
Subject: [PATCH] HBASE-4397  -ROOT-, .META. tables stay offline for too long
 in recovery phase after all RSs                are shutdown at the same time
 (Ming Ma)

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1226110 13f79535-47bb-0310-9956-ffa450edef68
---
 CHANGES.txt                                   |  2 ++
 .../hbase/master/AssignmentManager.java       | 20 ++++++++++++++++++-
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/CHANGES.txt b/CHANGES.txt
index b1b48b20613..5fe100a7d9d 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -466,6 +466,8 @@ Release 0.92.0 - Unreleased
    HBASE-5099  ZK event thread waiting for root region assignment may block server
                shutdown handler for the region sever the root region was on (Jimmy)
    HBASE-5100  Rollback of split could cause closed region to be opened again (Chunhui)
+   HBASE-4397  -ROOT-, .META. tables stay offline for too long in recovery phase after all RSs
+               are shutdown at the same time (Ming Ma)
 
   TESTS
    HBASE-4450  test for number of blocks read: to serve as baseline for expected
diff --git a/src/main/java/org/apache/hadoop/hbase/master/AssignmentManager.java b/src/main/java/org/apache/hadoop/hbase/master/AssignmentManager.java
index cdfefb59ceb..35c4e9f8006 100644
--- a/src/main/java/org/apache/hadoop/hbase/master/AssignmentManager.java
+++ b/src/main/java/org/apache/hadoop/hbase/master/AssignmentManager.java
@@ -191,7 +191,7 @@ public class AssignmentManager extends ZooKeeperListener {
     Configuration conf = master.getConfiguration();
     this.timeoutMonitor = new TimeoutMonitor(
       conf.getInt("hbase.master.assignment.timeoutmonitor.period", 10000),
-      master,
+      master, serverManager,
       conf.getInt("hbase.master.assignment.timeoutmonitor.timeout", 1800000));
     Threads.setDaemonThreadRunning(timeoutMonitor.getThread(),
       master.getServerName() + ".timeoutMonitor");
@@ -1498,6 +1498,7 @@ public class AssignmentManager extends ZooKeeperListener {
         state.update(RegionState.State.OFFLINE);
         // Force a new plan and reassign.  Will return null if no servers.
         if (getRegionPlan(state, plan.getDestination(), true) == null) {
+          this.timeoutMonitor.setAllRegionServersOffline(true);
           LOG.warn("Unable to find a viable location to assign region " +
             state.getRegion().getRegionNameAsString());
           return;
@@ -2512,6 +2513,8 @@ public class AssignmentManager extends ZooKeeperListener {
   public class TimeoutMonitor extends Chore {
     private final int timeout;
     private boolean bulkAssign = false;
+    private boolean allRegionServersOffline = false;
+    private ServerManager serverManager;
 
     /**
      * Creates a periodic monitor to check for time outs on region transition
@@ -2523,9 +2526,11 @@ public class AssignmentManager extends ZooKeeperListener {
      * @param timeout
      */
     public TimeoutMonitor(final int period, final Stoppable stopper,
+        ServerManager serverManager,
         final int timeout) {
       super("AssignmentTimeoutMonitor", period, stopper);
       this.timeout = timeout;
+      this.serverManager = serverManager;
     }
 
     /**
@@ -2539,10 +2544,18 @@ public class AssignmentManager extends ZooKeeperListener {
       return result;
     }
 
+    private synchronized void setAllRegionServersOffline(
+      boolean allRegionServersOffline) {
+      this.allRegionServersOffline = allRegionServersOffline;
+    }
+
     @Override
     protected void chore() {
       // If bulkAssign in progress, suspend checks
       if (this.bulkAssign) return;
+      boolean allRSsOffline = this.serverManager.getOnlineServersList().
+        isEmpty();
+
       synchronized (regionsInTransition) {
         // Iterate all regions in transition checking for time outs
         long now = System.currentTimeMillis();
@@ -2550,9 +2563,14 @@ public class AssignmentManager extends ZooKeeperListener {
           if (regionState.getStamp() + timeout <= now) {
            //decide on action upon timeout
             actOnTimeOut(regionState);
+          } else if (this.allRegionServersOffline && !allRSsOffline) {
+            // if some RSs just came back online, we can start the
+            // the assignment right away
+            actOnTimeOut(regionState);
           }
         }
       }
+      setAllRegionServersOffline(allRSsOffline);
     }
 
     private void actOnTimeOut(RegionState regionState) {