HBASE-24958 CompactingMemStore.timeOfOldestEdit error update (#2321)

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

@@ -80,6 +80,7 @@ public abstract class AbstractMemStore implements MemStore {
     this.comparator = c;
     this.regionServices = regionServices;
     resetActive();
+    resetTimeOfOldestEdit();
     this.snapshot = SegmentFactory.instance().createImmutableSegment(c);
     this.snapshotId = NO_SNAPSHOT_ID;
   }
@@ -95,7 +96,10 @@ public abstract class AbstractMemStore implements MemStore {
         memstoreAccounting.getHeapSize(), memstoreAccounting.getOffHeapSize(),
         memstoreAccounting.getCellsCount());
     }
-    timeOfOldestEdit = Long.MAX_VALUE;
+  }
+
+  protected void resetTimeOfOldestEdit() {
+    this.timeOfOldestEdit = Long.MAX_VALUE;
   }
 
   /**

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

@@ -212,6 +212,7 @@ public class CompactingMemStore extends AbstractMemStore {
       // region level lock ensures pushing active to pipeline is done in isolation
       // no concurrent update operations trying to flush the active segment
       pushActiveToPipeline(getActive());
+      resetTimeOfOldestEdit();
       snapshotId = EnvironmentEdgeManager.currentTime();
       // in both cases whatever is pushed to snapshot is cleared from the pipeline
       if (compositeSnapshot) {

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

@@ -109,6 +109,7 @@ public class DefaultMemStore extends AbstractMemStore {
         }
         this.snapshot = immutableSegment;
         resetActive();
+        resetTimeOfOldestEdit();
       }
     }
     return new MemStoreSnapshot(this.snapshotId, this.snapshot);

hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestCompactingMemStore.java

@@ -18,6 +18,7 @@
 package org.apache.hadoop.hbase.regionserver;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
@@ -131,6 +132,29 @@ public class TestCompactingMemStore extends TestDefaultMemStore {
     assertNotNull(chunkCreator);
   }
 
+  /**
+   * A simple test which flush in memory affect timeOfOldestEdit
+   */
+  @Test
+  public void testTimeOfOldestEdit() {
+    assertEquals(Long.MAX_VALUE,  memstore.timeOfOldestEdit());
+    final byte[] r = Bytes.toBytes("r");
+    final byte[] f = Bytes.toBytes("f");
+    final byte[] q = Bytes.toBytes("q");
+    final byte[] v = Bytes.toBytes("v");
+    final KeyValue kv = new KeyValue(r, f, q, v);
+    memstore.add(kv, null);
+    long timeOfOldestEdit = memstore.timeOfOldestEdit();
+    assertNotEquals(Long.MAX_VALUE, timeOfOldestEdit);
+
+    ((CompactingMemStore)memstore).flushInMemory();
+    assertEquals(timeOfOldestEdit, memstore.timeOfOldestEdit());
+    memstore.add(kv, null);
+    assertEquals(timeOfOldestEdit, memstore.timeOfOldestEdit());
+    memstore.snapshot();
+    assertEquals(Long.MAX_VALUE, memstore.timeOfOldestEdit());
+  }
+
   /**
    * A simple test which verifies the 3 possible states when scanning across snapshot.
    *