HBASE-25277 postScannerFilterRow impacts Scan performance a lot in HB…

…ase 2.x (apache#2765)

Signed-off-by: Guanghao Zhang <zghao@apache.org>
(cherry picked from commit 4cd6047)

Change-Id: I4f94ed20ca6d698e1a5bef221a8efd39192a1cb9

hbase-server/src/main/java/org/apache/hadoop/hbase/constraint/ConstraintProcessor.java

@@ -22,20 +22,19 @@
 import java.util.List;
 import java.util.Optional;
 
-import org.apache.yetus.audience.InterfaceAudience;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CoprocessorEnvironment;
-import org.apache.hadoop.hbase.client.Put;
 import org.apache.hadoop.hbase.client.Durability;
+import org.apache.hadoop.hbase.client.Put;
 import org.apache.hadoop.hbase.client.TableDescriptor;
 import org.apache.hadoop.hbase.coprocessor.ObserverContext;
 import org.apache.hadoop.hbase.coprocessor.RegionCoprocessor;
 import org.apache.hadoop.hbase.coprocessor.RegionCoprocessorEnvironment;
 import org.apache.hadoop.hbase.coprocessor.RegionObserver;
-import org.apache.hadoop.hbase.regionserver.InternalScanner;
 import org.apache.hadoop.hbase.wal.WALEdit;
+import org.apache.yetus.audience.InterfaceAudience;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /***
  * Processes multiple {@link Constraint Constraints} on a given table.
@@ -98,11 +97,4 @@ public void prePut(ObserverContext<RegionCoprocessorEnvironment> e, Put put,
     }
     // if we made it here, then the Put is valid
   }
-
-  @Override
-  public boolean postScannerFilterRow(final ObserverContext<RegionCoprocessorEnvironment> e,
-      final InternalScanner s, final Cell curRowCell, final boolean hasMore) throws IOException {
-    // 'default' in RegionObserver might do unnecessary copy for Off heap backed Cells.
-    return hasMore;
-  }
 }

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

@@ -105,6 +105,13 @@ public class RegionCoprocessorHost
   // optimization: no need to call postScannerFilterRow, if no coprocessor implements it
   private final boolean hasCustomPostScannerFilterRow;
 
+  /*
+   * Whether any configured CPs override postScannerFilterRow hook
+   */
+  public boolean hasCustomPostScannerFilterRow() {
+    return hasCustomPostScannerFilterRow;
+  }
+
   /**
    *
    * Encapsulation of the environment of each coprocessor
@@ -278,11 +285,10 @@ public RegionCoprocessorHost(final HRegion region,
     out: for (RegionCoprocessorEnvironment env: coprocEnvironments) {
       if (env.getInstance() instanceof RegionObserver) {
         Class<?> clazz = env.getInstance().getClass();
-        for(;;) {
-          if (clazz == null) {
-            // we must have directly implemented RegionObserver
-            hasCustomPostScannerFilterRow = true;
-            break out;
+        for (;;) {
+          if (clazz == Object.class) {
+            // we dont need to look postScannerFilterRow into Object class
+            break; // break the inner loop
           }
           try {
             clazz.getDeclaredMethod("postScannerFilterRow", ObserverContext.class,

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

@@ -1877,13 +1877,6 @@ public void postScannerClose(final ObserverContext<RegionCoprocessorEnvironment>
     scannerOwners.remove(s);
   }
 
-  @Override
-  public boolean postScannerFilterRow(final ObserverContext<RegionCoprocessorEnvironment> e,
-      final InternalScanner s, final Cell curRowCell, final boolean hasMore) throws IOException {
-    // 'default' in RegionObserver might do unnecessary copy for Off heap backed Cells.
-    return hasMore;
-  }
-
   /**
    * Verify, when servicing an RPC, that the caller is the scanner owner.
    * If so, we assume that access control is correctly enforced based on

hbase-server/src/main/java/org/apache/hadoop/hbase/security/visibility/VisibilityController.java

@@ -741,13 +741,6 @@ private Cell createNewCellWithTags(Mutation mutation, Cell newCell) throws IOExc
     return PrivateCellUtil.createCell(newCell, tags);
   }
 
-  @Override
-  public boolean postScannerFilterRow(final ObserverContext<RegionCoprocessorEnvironment> e,
-      final InternalScanner s, final Cell curRowCell, final boolean hasMore) throws IOException {
-    // 'default' in RegionObserver might do unnecessary copy for Off heap backed Cells.
-    return hasMore;
-  }
-
   /****************************** VisibilityEndpoint service related methods ******************************/
   @Override
   public synchronized void addLabels(RpcController controller, VisibilityLabelsRequest request,

hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestRegionCoprocessorHost.java

@@ -37,6 +37,7 @@
 import org.apache.hadoop.hbase.regionserver.RegionCoprocessorHost;
 import org.apache.hadoop.hbase.regionserver.RegionServerServices;
 import org.apache.hadoop.hbase.testclassification.SmallTests;
+
 import org.junit.ClassRule;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;