HBASE-26268: Provide coprocessor hooks for updateConfiguration and clearRegionBlockCache

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

@@ -46,16 +46,19 @@
 import org.apache.hadoop.hbase.conf.ConfigurationManager;
 import org.apache.hadoop.hbase.conf.ConfigurationObserver;
 import org.apache.hadoop.hbase.coordination.ZkCoordinatedStateManager;
+import org.apache.hadoop.hbase.coprocessor.CoprocessorHost;
 import org.apache.hadoop.hbase.executor.ExecutorService;
 import org.apache.hadoop.hbase.fs.HFileSystem;
 import org.apache.hadoop.hbase.http.InfoServer;
 import org.apache.hadoop.hbase.io.util.MemorySizeUtil;
 import org.apache.hadoop.hbase.ipc.RpcServerInterface;
 import org.apache.hadoop.hbase.master.HMaster;
+import org.apache.hadoop.hbase.master.MasterCoprocessorHost;
 import org.apache.hadoop.hbase.namequeues.NamedQueueRecorder;
 import org.apache.hadoop.hbase.regionserver.ChunkCreator;
 import org.apache.hadoop.hbase.regionserver.HeapMemoryManager;
 import org.apache.hadoop.hbase.regionserver.MemStoreLAB;
+import org.apache.hadoop.hbase.regionserver.RegionServerCoprocessorHost;
 import org.apache.hadoop.hbase.regionserver.ShutdownHook;
 import org.apache.hadoop.hbase.security.Superusers;
 import org.apache.hadoop.hbase.security.User;
@@ -184,14 +187,14 @@ public abstract class HBaseServerBase<R extends HBaseRpcServicesBase<?>> extends
 
   protected final NettyEventLoopGroupConfig eventLoopGroupConfig;
 
-  /**
-   * If running on Windows, do windows-specific setup.
-   */
-  private static void setupWindows(final Configuration conf, ConfigurationManager cm) {
+  private void setupSignalHandlers() {
     if (!SystemUtils.IS_OS_WINDOWS) {
       HBasePlatformDependent.handle("HUP", (number, name) -> {
-        conf.reloadConfiguration();
-        cm.notifyAllObservers(conf);
+        try {
+          updateConfiguration();
+        } catch (IOException e) {
+          LOG.error("Problem while reloading configuration", e);
+        }
       });
     }
   }
@@ -276,7 +279,7 @@ public HBaseServerBase(Configuration conf, String name) throws IOException {
         new ZKWatcher(conf, getProcessName() + ":" + addr.getPort(), this, canCreateBaseZNode());
 
       this.configurationManager = new ConfigurationManager();
-      setupWindows(conf, configurationManager);
+      setupSignalHandlers();
 
       initializeFileSystem();
 
@@ -614,18 +617,40 @@ public ConfigurationManager getConfigurationManager() {
   /**
    * Reload the configuration from disk.
    */
-  public void updateConfiguration() {
+  public void updateConfiguration() throws IOException {
     LOG.info("Reloading the configuration from disk.");
     // Reload the configuration from disk.
+    preUpdateConfiguration();
     conf.reloadConfiguration();
     configurationManager.notifyAllObservers(conf);
+    postUpdateConfiguration();
+  }
+
+  private void preUpdateConfiguration() throws IOException {
+    CoprocessorHost<?, ?> coprocessorHost = getCoprocessorHost();
+    if (coprocessorHost instanceof RegionServerCoprocessorHost) {
+      ((RegionServerCoprocessorHost) coprocessorHost).preUpdateConfiguration(conf);
+    } else if (coprocessorHost instanceof MasterCoprocessorHost) {
+      ((MasterCoprocessorHost) coprocessorHost).preUpdateConfiguration(conf);
+    }
+  }
+
+  private void postUpdateConfiguration() throws IOException {
+    CoprocessorHost<?, ?> coprocessorHost = getCoprocessorHost();
+    if (coprocessorHost instanceof RegionServerCoprocessorHost) {
+      ((RegionServerCoprocessorHost) coprocessorHost).postUpdateConfiguration(conf);
+    } else if (coprocessorHost instanceof MasterCoprocessorHost) {
+      ((MasterCoprocessorHost) coprocessorHost).postUpdateConfiguration(conf);
+    }
   }
 
   @Override
   public String toString() {
     return getServerName().toString();
   }
 
+  protected abstract CoprocessorHost<?, ?> getCoprocessorHost();
+
   protected abstract boolean canCreateBaseZNode();
 
   protected abstract String getProcessName();

hbase-server/src/main/java/org/apache/hadoop/hbase/coprocessor/MasterObserver.java

@@ -21,6 +21,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.ClusterMetrics;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.MetaMutationAnnotation;
@@ -1873,4 +1874,24 @@ default void preHasUserPermissions(ObserverContext<MasterCoprocessorEnvironment>
   default void postHasUserPermissions(ObserverContext<MasterCoprocessorEnvironment> ctx,
     String userName, List<Permission> permissions) throws IOException {
   }
+
+  /**
+   * Called before reloading the HMaster's {@link Configuration} from disk
+   * @param ctx           the coprocessor instance's environment
+   * @param preReloadConf the {@link Configuration} in use prior to reload
+   * @throws IOException if you need to signal an IO error
+   */
+  default void preUpdateMasterConfiguration(ObserverContext<MasterCoprocessorEnvironment> ctx,
+    Configuration preReloadConf) throws IOException {
+  }
+
+  /**
+   * Called after reloading the HMaster's {@link Configuration} from disk
+   * @param ctx            the coprocessor instance's environment
+   * @param postReloadConf the {@link Configuration} that was loaded
+   * @throws IOException if you need to signal an IO error
+   */
+  default void postUpdateMasterConfiguration(ObserverContext<MasterCoprocessorEnvironment> ctx,
+    Configuration postReloadConf) throws IOException {
+  }
 }

hbase-server/src/main/java/org/apache/hadoop/hbase/coprocessor/RegionServerObserver.java

@@ -18,6 +18,8 @@
 package org.apache.hadoop.hbase.coprocessor;
 
 import java.io.IOException;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.CacheEvictionStats;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.client.Mutation;
 import org.apache.hadoop.hbase.replication.ReplicationEndpoint;
@@ -169,4 +171,45 @@ default void postReplicationSinkBatchMutate(
 
   }
 
+  /**
+   * Called before clearing the block caches for one or more regions
+   * @param ctx the coprocessor instance's environment
+   * @throws IOException if you need to signal an IO error
+   */
+  default void preClearRegionBlockCache(ObserverContext<RegionServerCoprocessorEnvironment> ctx)
+    throws IOException {
+  }
+
+  /**
+   * Called after clearing the block caches for one or more regions
+   * @param ctx   the coprocessor instance's environment
+   * @param stats statistics about the cache evictions that happened
+   * @throws IOException if you need to signal an IO error
+   */
+  default void postClearRegionBlockCache(ObserverContext<RegionServerCoprocessorEnvironment> ctx,
+    CacheEvictionStats stats) throws IOException {
+  }
+
+  /**
+   * Called before reloading the RegionServer's {@link Configuration} from disk
+   * @param ctx           the coprocessor instance's environment
+   * @param preReloadConf the {@link Configuration} in use prior to reload
+   * @throws IOException if you need to signal an IO error
+   */
+  default void preUpdateRegionServerConfiguration(
+    ObserverContext<RegionServerCoprocessorEnvironment> ctx, Configuration preReloadConf)
+    throws IOException {
+  }
+
+  /**
+   * Called after reloading the RegionServer's {@link Configuration} from disk
+   * @param ctx            the coprocessor instance's environment
+   * @param postReloadConf the {@link Configuration} that was loaded
+   * @throws IOException if you need to signal an IO error
+   */
+  default void postUpdateRegionServerConfiguration(
+    ObserverContext<RegionServerCoprocessorEnvironment> ctx, Configuration postReloadConf)
+    throws IOException {
+  }
+
 }

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

@@ -724,6 +724,11 @@ public MasterRpcServices getMasterRpcServices() {
     return rpcServices;
   }
 
+  @Override
+  protected MasterCoprocessorHost getCoprocessorHost() {
+    return getMasterCoprocessorHost();
+  }
+
   public boolean balanceSwitch(final boolean b) throws IOException {
     return getMasterRpcServices().switchBalancer(b, BalanceSwitchMode.ASYNC);
   }

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

@@ -2114,4 +2114,22 @@ public void call(MasterObserver observer) throws IOException {
       }
     });
   }
+
+  public void preUpdateConfiguration(Configuration preReloadConf) throws IOException {
+    execOperation(coprocEnvironments.isEmpty() ? null : new MasterObserverOperation() {
+      @Override
+      public void call(MasterObserver observer) throws IOException {
+        observer.preUpdateMasterConfiguration(this, preReloadConf);
+      }
+    });
+  }
+
+  public void postUpdateConfiguration(Configuration postReloadConf) throws IOException {
+    execOperation(coprocEnvironments.isEmpty() ? null : new MasterObserverOperation() {
+      @Override
+      public void call(MasterObserver observer) throws IOException {
+        observer.postUpdateMasterConfiguration(this, postReloadConf);
+      }
+    });
+  }
 }

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

@@ -587,6 +587,11 @@ protected String getProcessName() {
     return REGIONSERVER;
   }
 
+  @Override
+  protected RegionServerCoprocessorHost getCoprocessorHost() {
+    return getRegionServerCoprocessorHost();
+  }
+
   @Override
   protected boolean canCreateBaseZNode() {
     return !clusterMode();

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

@@ -3802,19 +3802,25 @@ public GetSpaceQuotaSnapshotsResponse getSpaceQuotaSnapshots(RpcController contr
   @Override
   public ClearRegionBlockCacheResponse clearRegionBlockCache(RpcController controller,
     ClearRegionBlockCacheRequest request) throws ServiceException {
-    rpcPreCheck("clearRegionBlockCache");
-    ClearRegionBlockCacheResponse.Builder builder = ClearRegionBlockCacheResponse.newBuilder();
-    CacheEvictionStatsBuilder stats = CacheEvictionStats.builder();
-    List<HRegion> regions = getRegions(request.getRegionList(), stats);
-    for (HRegion region : regions) {
-      try {
-        stats = stats.append(this.server.clearRegionBlockCache(region));
-      } catch (Exception e) {
-        stats.addException(region.getRegionInfo().getRegionName(), e);
+    try {
+      rpcPreCheck("clearRegionBlockCache");
+      ClearRegionBlockCacheResponse.Builder builder = ClearRegionBlockCacheResponse.newBuilder();
+      CacheEvictionStatsBuilder stats = CacheEvictionStats.builder();
+      server.getRegionServerCoprocessorHost().preClearRegionBlockCache();
+      List<HRegion> regions = getRegions(request.getRegionList(), stats);
+      for (HRegion region : regions) {
+        try {
+          stats = stats.append(this.server.clearRegionBlockCache(region));
+        } catch (Exception e) {
+          stats.addException(region.getRegionInfo().getRegionName(), e);
+        }
       }
+      stats.withMaxCacheSize(server.getBlockCache().map(BlockCache::getMaxSize).orElse(0L));
+      server.getRegionServerCoprocessorHost().postClearRegionBlockCache(stats.build());
+      return builder.setStats(ProtobufUtil.toCacheEvictionStats(stats.build())).build();
+    } catch (IOException e) {
+      throw new ServiceException(e);
     }
-    stats.withMaxCacheSize(server.getBlockCache().map(BlockCache::getMaxSize).orElse(0L));
-    return builder.setStats(ProtobufUtil.toCacheEvictionStats(stats.build())).build();
   }
 
   private void executeOpenRegionProcedures(OpenRegionRequest request,

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

@@ -20,6 +20,7 @@
 import java.io.IOException;
 import java.lang.reflect.InvocationTargetException;
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.CacheEvictionStats;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.client.Connection;
 import org.apache.hadoop.hbase.client.Mutation;
@@ -240,6 +241,42 @@ public void call(RegionServerObserver observer) throws IOException {
     });
   }
 
+  public void preUpdateConfiguration(Configuration preReloadConf) throws IOException {
+    execOperation(coprocEnvironments.isEmpty() ? null : new RegionServerObserverOperation() {
+      @Override
+      public void call(RegionServerObserver observer) throws IOException {
+        observer.preUpdateRegionServerConfiguration(this, preReloadConf);
+      }
+    });
+  }
+
+  public void postUpdateConfiguration(Configuration postReloadConf) throws IOException {
+    execOperation(coprocEnvironments.isEmpty() ? null : new RegionServerObserverOperation() {
+      @Override
+      public void call(RegionServerObserver observer) throws IOException {
+        observer.postUpdateRegionServerConfiguration(this, postReloadConf);
+      }
+    });
+  }
+
+  public void preClearRegionBlockCache() throws IOException {
+    execOperation(coprocEnvironments.isEmpty() ? null : new RegionServerObserverOperation() {
+      @Override
+      public void call(RegionServerObserver observer) throws IOException {
+        observer.preClearRegionBlockCache(this);
+      }
+    });
+  }
+
+  public void postClearRegionBlockCache(CacheEvictionStats stats) throws IOException {
+    execOperation(coprocEnvironments.isEmpty() ? null : new RegionServerObserverOperation() {
+      @Override
+      public void call(RegionServerObserver observer) throws IOException {
+        observer.postClearRegionBlockCache(this, stats);
+      }
+    });
+  }
+
   /**
    * Coprocessor environment extension providing access to region server related services.
    */

hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/AccessController.java

@@ -2576,4 +2576,27 @@ public void preUpdateRSGroupConfig(final ObserverContext<MasterCoprocessorEnviro
     accessChecker.requirePermission(getActiveUser(ctx), "updateRSGroupConfig", null,
       Permission.Action.ADMIN);
   }
+
+  @Override
+  public void preClearRegionBlockCache(ObserverContext<RegionServerCoprocessorEnvironment> ctx)
+    throws IOException {
+    accessChecker.requirePermission(getActiveUser(ctx), "clearRegionBlockCache", null,
+      Permission.Action.ADMIN);
+  }
+
+  @Override
+  public void preUpdateRegionServerConfiguration(
+    ObserverContext<RegionServerCoprocessorEnvironment> ctx, Configuration preReloadConf)
+    throws IOException {
+    accessChecker.requirePermission(getActiveUser(ctx), "updateConfiguration", null,
+      Permission.Action.ADMIN);
+  }
+
+  @Override
+  public void preUpdateMasterConfiguration(ObserverContext<MasterCoprocessorEnvironment> ctx,
+    Configuration preReloadConf) throws IOException {
+    accessChecker.requirePermission(getActiveUser(ctx), "updateConfiguration", null,
+      Permission.Action.ADMIN);
+  }
+
 }