Cache more efficiently getAll() and get() in FSTableDescriptors

Signed-off-by: stack <stack@apache.org>

hbase-server/src/main/java/org/apache/hadoop/hbase/TableDescriptors.java

@@ -69,4 +69,14 @@ void add(final HTableDescriptor htd)
    */
   HTableDescriptor remove(final TableName tablename)
   throws IOException;
+
+  /**
+   * Enables the tabledescriptor cache
+   */
+  void setCacheOn() throws IOException;
+
+  /**
+   * Disables the tabledescriptor cache
+   */
+  void setCacheOff() throws IOException;
 }

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

@@ -214,6 +214,8 @@ public class HMaster extends HRegionServer implements MasterServices, Server {
 
   MasterCoprocessorHost cpHost;
 
+  private final boolean preLoadTableDescriptors;
+
   // Time stamps for when a hmaster became active
   private long masterActiveTime;
 
@@ -285,8 +287,11 @@ public HMaster(final Configuration conf, CoordinatedStateManager csm)
 
     this.metricsMaster = new MetricsMaster( new MetricsMasterWrapperImpl(this));
 
+    // preload table descriptor at startup
+    this.preLoadTableDescriptors = conf.getBoolean("hbase.master.preload.tabledescriptors", true);
+
     // Do we publish the status?
-    
+
     boolean shouldPublish = conf.getBoolean(HConstants.STATUS_PUBLISHED,
         HConstants.STATUS_PUBLISHED_DEFAULT);
     Class<? extends ClusterStatusPublisher.Publisher> publisherClass =
@@ -505,6 +510,15 @@ private void finishActiveMasterInitialization(MonitoredTask status)
     // TODO: Do this using Dependency Injection, using PicoContainer, Guice or Spring.
     this.fileSystemManager = new MasterFileSystem(this, this);
 
+    // enable table descriptors cache
+    this.tableDescriptors.setCacheOn();
+
+    // warm-up HTDs cache on master initialization
+    if (preLoadTableDescriptors) {
+      status.setStatus("Pre-loading table descriptors");
+      this.tableDescriptors.getAll();
+    }
+
     // publish cluster ID
     status.setStatus("Publishing Cluster ID in ZooKeeper");
     ZKClusterId.setClusterId(this.zooKeeper, fileSystemManager.getClusterId());

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

@@ -266,14 +266,17 @@ private void handleCreateTable(TableName tableName)
       ModifyRegionUtils.assignRegions(assignmentManager, regionInfos);
     }
 
-    // 6. Set table enabled flag up in zk.
+    // 7. Set table enabled flag up in zk.
     try {
       assignmentManager.getTableStateManager().setTableState(tableName,
         ZooKeeperProtos.Table.State.ENABLED);
     } catch (CoordinatedStateException e) {
       throw new IOException("Unable to ensure that " + tableName + " will be" +
         " enabled because of a ZooKeeper issue", e);
     }
+
+    // 8. Update the tabledescriptor cache.
+    ((HMaster) this.server).getTableDescriptors().get(tableName);
   }
 
   /**

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

@@ -97,9 +97,9 @@ private void recreateTable(final List<HRegionInfo> regions) throws IOException {
     CreateTableHandler.checkAndSetEnablingTable(assignmentManager, tableName);
     try {
       // 1. Create Table Descriptor
-      new FSTableDescriptors(server.getConfiguration())
-        .createTableDescriptorForTableDirectory(tempdir, this.hTableDescriptor, false);
       Path tempTableDir = FSUtils.getTableDir(tempdir, this.tableName);
+      new FSTableDescriptors(server.getConfiguration())
+        .createTableDescriptorForTableDirectory(tempTableDir, this.hTableDescriptor, false);
       Path tableDir = FSUtils.getTableDir(mfs.getRootDir(), this.tableName);
 
       HRegionInfo[] newRegions;

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java

@@ -514,7 +514,7 @@ public void uncaughtException(Thread t, Throwable e) {
     this.fs = new HFileSystem(this.conf, useHBaseChecksum);
     this.rootDir = FSUtils.getRootDir(this.conf);
     this.tableDescriptors = new FSTableDescriptors(
-      this.fs, this.rootDir, !canUpdateTableDescriptor());
+      this.fs, this.rootDir, !canUpdateTableDescriptor(), false);
 
     service = new ExecutorService(getServerName().toShortString());
     spanReceiverHost = SpanReceiverHost.getInstance(getConfiguration());
@@ -608,7 +608,7 @@ protected HConnection createShortCircuitConnection() throws IOException {
     return ConnectionUtils.createShortCircuitHConnection(
       HConnectionManager.getConnection(conf), serverName, rpcServices, rpcServices);
   }
-  
+
   /**
    * Run test on configured codecs to make sure supporting libs are in place.
    * @param c
@@ -3011,7 +3011,7 @@ private String getLastFailedRSFromZK(String encodedRegionName) throws KeeperExce
     }
     return result;
   }
-  
+
   public CoprocessorServiceResponse execRegionServerService(final RpcController controller,
       final CoprocessorServiceRequest serviceRequest) throws ServiceException {
     try {
@@ -3058,7 +3058,7 @@ public void run(Message message) {
       throw new ServiceException(ie);
     }
   }
-  
+
   /**
    * @return The cache config instance used by the regionserver.
    */
@@ -3072,14 +3072,14 @@ public CacheConfig getCacheConfig() {
   protected ConfigurationManager getConfigurationManager() {
     return configurationManager;
   }
-    
+
   /**
    * Reload the configuration from disk.
    */
   public void updateConfiguration() {
     LOG.info("Reloading the configuration from disk.");
     // Reload the configuration from disk.
     conf.reloadConfiguration();
-    configurationManager.notifyAllObservers(conf);  
+    configurationManager.notifyAllObservers(conf);
   }
 }