HBASE-14273 Rename MVCC to MVCC: From MultiVersionConsistencyControl to MultiVersionConcurrencyControl (Lars Francke)

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

@@ -146,7 +146,7 @@ import org.apache.hadoop.hbase.protobuf.generated.WALProtos.FlushDescriptor.Stor
 import org.apache.hadoop.hbase.protobuf.generated.WALProtos.RegionEventDescriptor;
 import org.apache.hadoop.hbase.protobuf.generated.WALProtos.RegionEventDescriptor.EventType;
 import org.apache.hadoop.hbase.protobuf.generated.WALProtos.StoreDescriptor;
-import org.apache.hadoop.hbase.regionserver.MultiVersionConsistencyControl.WriteEntry;
+import org.apache.hadoop.hbase.regionserver.MultiVersionConcurrencyControl.WriteEntry;
 import org.apache.hadoop.hbase.regionserver.ScannerContext.LimitScope;
 import org.apache.hadoop.hbase.regionserver.ScannerContext.NextState;
 import org.apache.hadoop.hbase.regionserver.compactions.CompactionContext;
@@ -584,8 +584,8 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
   private boolean splitRequest;
   private byte[] explicitSplitPoint = null;
 
-  private final MultiVersionConsistencyControl mvcc =
+  private final MultiVersionConcurrencyControl mvcc =
-      new MultiVersionConsistencyControl();
+      new MultiVersionConcurrencyControl();
 
   // Coprocessor host
   private RegionCoprocessorHost coprocessorHost;
@@ -1252,7 +1252,7 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
     }
   }
 
-   public MultiVersionConsistencyControl getMVCC() {
+   public MultiVersionConcurrencyControl getMVCC() {
      return mvcc;
    }
 
@@ -2081,7 +2081,7 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
     if (this.memstoreSize.get() <= 0) {
       // Take an update lock because am about to change the sequence id and we want the sequence id
       // to be at the border of the empty memstore.
-      MultiVersionConsistencyControl.WriteEntry w = null;
+      MultiVersionConcurrencyControl.WriteEntry w = null;
       this.updatesLock.writeLock().lock();
       try {
         if (this.memstoreSize.get() <= 0) {
@@ -2137,7 +2137,7 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
     // to do this for a moment.  It is quick. We also set the memstore size to zero here before we
     // allow updates again so its value will represent the size of the updates received
     // during flush
-    MultiVersionConsistencyControl.WriteEntry w = null;
+    MultiVersionConcurrencyControl.WriteEntry w = null;
     // We have to take an update lock during snapshot, or else a write could end up in both snapshot
     // and memstore (makes it difficult to do atomic rows then)
     status.setStatus("Obtaining lock to block concurrent updates");
@@ -2853,7 +2853,7 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
 
     long currentNonceGroup = HConstants.NO_NONCE, currentNonce = HConstants.NO_NONCE;
     WALEdit walEdit = new WALEdit(isInReplay);
-    MultiVersionConsistencyControl.WriteEntry w = null;
+    MultiVersionConcurrencyControl.WriteEntry w = null;
     long txid = 0;
     boolean doRollBackMemstore = false;
     boolean locked = false;
@@ -3000,7 +3000,7 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
       if(isInReplay) {
         mvccNum = batchOp.getReplaySequenceId();
       } else {
-        mvccNum = MultiVersionConsistencyControl.getPreAssignedWriteNumber(this.sequenceId);
+        mvccNum = MultiVersionConcurrencyControl.getPreAssignedWriteNumber(this.sequenceId);
       }
       //
       // ------------------------------------
@@ -6635,7 +6635,7 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
       return;
     }
 
-    MultiVersionConsistencyControl.WriteEntry writeEntry = null;
+    MultiVersionConcurrencyControl.WriteEntry writeEntry = null;
     boolean locked;
     boolean walSyncSuccessful = false;
     List<RowLock> acquiredRowLocks;
@@ -6656,7 +6656,7 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
       lock(this.updatesLock.readLock(), acquiredRowLocks.size() == 0 ? 1 : acquiredRowLocks.size());
       locked = true;
       // Get a mvcc write number
-      mvccNum = MultiVersionConsistencyControl.getPreAssignedWriteNumber(this.sequenceId);
+      mvccNum = MultiVersionConcurrencyControl.getPreAssignedWriteNumber(this.sequenceId);
 
       long now = EnvironmentEdgeManager.currentTime();
       try {
@@ -6853,7 +6853,7 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
             }
           }
           // now start my own transaction
-          mvccNum = MultiVersionConsistencyControl.getPreAssignedWriteNumber(this.sequenceId);
+          mvccNum = MultiVersionConcurrencyControl.getPreAssignedWriteNumber(this.sequenceId);
           w = mvcc.beginMemstoreInsertWithSeqNum(mvccNum);
           long now = EnvironmentEdgeManager.currentTime();
           // Process each family
@@ -7106,7 +7106,7 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
             }
           }
           // now start my own transaction
-          mvccNum = MultiVersionConsistencyControl.getPreAssignedWriteNumber(this.sequenceId);
+          mvccNum = MultiVersionConcurrencyControl.getPreAssignedWriteNumber(this.sequenceId);
           w = mvcc.beginMemstoreInsertWithSeqNum(mvccNum);
           long now = EnvironmentEdgeManager.currentTime();
           // Process each family
@@ -7332,7 +7332,7 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
       WriteState.HEAP_SIZE + // writestate
       ClassSize.CONCURRENT_SKIPLISTMAP + ClassSize.CONCURRENT_SKIPLISTMAP_ENTRY + // stores
       (2 * ClassSize.REENTRANT_LOCK) + // lock, updatesLock
-      MultiVersionConsistencyControl.FIXED_SIZE // mvcc
+      MultiVersionConcurrencyControl.FIXED_SIZE // mvcc
       + ClassSize.TREEMAP // maxSeqIdInStores
       + 2 * ClassSize.ATOMIC_INTEGER // majorInProgress, minorInProgress
       ;

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

@@ -33,7 +33,7 @@ import org.apache.hadoop.hbase.util.ClassSize;
  * the new writes for readers to read (thus forming atomic transactions).
  */
 @InterfaceAudience.Private
-public class MultiVersionConsistencyControl {
+public class MultiVersionConcurrencyControl {
   private static final long NO_WRITE_NUMBER = 0;
   private volatile long memstoreRead = 0;
   private final Object readWaiters = new Object();
@@ -45,7 +45,7 @@ public class MultiVersionConsistencyControl {
   /**
    * Default constructor. Initializes the memstoreRead/Write points to 0.
    */
-  public MultiVersionConsistencyControl() {
+  public MultiVersionConcurrencyControl() {
   }
 
   /**

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

@@ -63,7 +63,7 @@ public interface RegionScanner extends InternalScanner, Shipper {
   long getMaxResultSize();
 
   /**
-   * @return The Scanner's MVCC readPt see {@link MultiVersionConsistencyControl}
+   * @return The Scanner's MVCC readPt see {@link MultiVersionConcurrencyControl}
    */
   long getMvccReadPoint();
 
@@ -94,7 +94,7 @@ public interface RegionScanner extends InternalScanner, Shipper {
    * close a region operation, an synchronize on the scanner object. Example: <code>
    * HRegion region = ...;
    * RegionScanner scanner = ...
-   * MultiVersionConsistencyControl.setThreadReadPoint(scanner.getMvccReadPoint());
+   * MultiVersionConcurrencyControl.setThreadReadPoint(scanner.getMvccReadPoint());
    * region.startRegionOperation();
    * try {
    *   synchronized(scanner) {

hbase-server/src/test/java/org/apache/hadoop/hbase/HBaseTestingUtility.java

@@ -3538,7 +3538,7 @@ public class HBaseTestingUtility extends HBaseCommonTestingUtility {
     Scan scan = new Scan(get);
     InternalScanner scanner = (InternalScanner) store.getScanner(scan,
         scan.getFamilyMap().get(store.getFamily().getName()),
-        // originally MultiVersionConsistencyControl.resetThreadReadPoint() was called to set
+        // originally MultiVersionConcurrencyControl.resetThreadReadPoint() was called to set
         // readpoint 0.
         0);
 

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

@@ -69,13 +69,13 @@ public class TestDefaultMemStore extends TestCase {
   private static final int ROW_COUNT = 10;
   private static final int QUALIFIER_COUNT = ROW_COUNT;
   private static final byte [] FAMILY = Bytes.toBytes("column");
-  private MultiVersionConsistencyControl mvcc;
+  private MultiVersionConcurrencyControl mvcc;
   private AtomicLong startSeqNum = new AtomicLong(0);
 
   @Override
   public void setUp() throws Exception {
     super.setUp();
-    this.mvcc = new MultiVersionConsistencyControl();
+    this.mvcc = new MultiVersionConcurrencyControl();
     this.memstore = new DefaultMemStore();
   }
 
@@ -248,7 +248,7 @@ public class TestDefaultMemStore extends TestCase {
     final byte[] q2 = Bytes.toBytes("q2");
     final byte[] v = Bytes.toBytes("value");
 
-    MultiVersionConsistencyControl.WriteEntry w =
+    MultiVersionConcurrencyControl.WriteEntry w =
         mvcc.beginMemstoreInsertWithSeqNum(this.startSeqNum.incrementAndGet());
 
     KeyValue kv1 = new KeyValue(row, f, q1, v);
@@ -292,7 +292,7 @@ public class TestDefaultMemStore extends TestCase {
     final byte[] v2 = Bytes.toBytes("value2");
 
     // INSERT 1: Write both columns val1
-    MultiVersionConsistencyControl.WriteEntry w =
+    MultiVersionConcurrencyControl.WriteEntry w =
         mvcc.beginMemstoreInsertWithSeqNum(this.startSeqNum.incrementAndGet());
 
     KeyValue kv11 = new KeyValue(row, f, q1, v1);
@@ -344,7 +344,7 @@ public class TestDefaultMemStore extends TestCase {
     final byte[] q2 = Bytes.toBytes("q2");
     final byte[] v1 = Bytes.toBytes("value1");
     // INSERT 1: Write both columns val1
-    MultiVersionConsistencyControl.WriteEntry w =
+    MultiVersionConcurrencyControl.WriteEntry w =
         mvcc.beginMemstoreInsertWithSeqNum(this.startSeqNum.incrementAndGet());
 
     KeyValue kv11 = new KeyValue(row, f, q1, v1);
@@ -388,7 +388,7 @@ public class TestDefaultMemStore extends TestCase {
     final byte[] f = Bytes.toBytes("family");
     final byte[] q1 = Bytes.toBytes("q1");
 
-    final MultiVersionConsistencyControl mvcc;
+    final MultiVersionConcurrencyControl mvcc;
     final MemStore memstore;
     final AtomicLong startSeqNum;
 
@@ -397,7 +397,7 @@ public class TestDefaultMemStore extends TestCase {
 
     public ReadOwnWritesTester(int id,
                                MemStore memstore,
-                               MultiVersionConsistencyControl mvcc,
+                               MultiVersionConcurrencyControl mvcc,
                                AtomicReference<Throwable> caughtException,
                                AtomicLong startSeqNum)
     {
@@ -418,7 +418,7 @@ public class TestDefaultMemStore extends TestCase {
 
     private void internalRun() throws IOException {
       for (long i = 0; i < NUM_TRIES && caughtException.get() == null; i++) {
-        MultiVersionConsistencyControl.WriteEntry w =
+        MultiVersionConcurrencyControl.WriteEntry w =
             mvcc.beginMemstoreInsertWithSeqNum(this.startSeqNum.incrementAndGet());
 
         // Insert the sequence value (i)

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

@@ -27,17 +27,17 @@ import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicLong;
 
 /**
- * This is a hammer test that verifies MultiVersionConsistencyControl in a
+ * This is a hammer test that verifies MultiVersionConcurrencyControl in a
  * multiple writer single reader scenario.
  */
 @Category({RegionServerTests.class, SmallTests.class})
-public class TestMultiVersionConsistencyControl extends TestCase {
+public class TestMultiVersionConcurrencyControl extends TestCase {
   static class Writer implements Runnable {
     final AtomicBoolean finished;
-    final MultiVersionConsistencyControl mvcc;
+    final MultiVersionConcurrencyControl mvcc;
     final AtomicBoolean status;
 
-    Writer(AtomicBoolean finished, MultiVersionConsistencyControl mvcc, AtomicBoolean status) {
+    Writer(AtomicBoolean finished, MultiVersionConcurrencyControl mvcc, AtomicBoolean status) {
       this.finished = finished;
       this.mvcc = mvcc;
       this.status = status;
@@ -49,7 +49,7 @@ public class TestMultiVersionConsistencyControl extends TestCase {
     public void run() {
       AtomicLong startPoint = new AtomicLong();
       while (!finished.get()) {
-        MultiVersionConsistencyControl.WriteEntry e = 
+        MultiVersionConcurrencyControl.WriteEntry e =
             mvcc.beginMemstoreInsertWithSeqNum(startPoint.incrementAndGet());
         // System.out.println("Begin write: " + e.getWriteNumber());
         // 10 usec - 500usec (including 0)
@@ -75,7 +75,7 @@ public class TestMultiVersionConsistencyControl extends TestCase {
   }
 
   public void testParallelism() throws Exception {
-    final MultiVersionConsistencyControl mvcc = new MultiVersionConsistencyControl();
+    final MultiVersionConcurrencyControl mvcc = new MultiVersionConcurrencyControl();
 
     final AtomicBoolean finished = new AtomicBoolean(false);
 

src/main/asciidoc/_chapters/architecture.adoc

@@ -1495,7 +1495,7 @@ The minimum flush unit is per region, not at individual MemStore level.
 * The `RegionScanner` object contains a list of `StoreScanner` objects, one per column family.
 * Each `StoreScanner` object further contains a list of `StoreFileScanner` objects, corresponding to each StoreFile and HFile of the corresponding column family, and a list of `KeyValueScanner` objects for the MemStore.
 * The two lists are merged into one, which is sorted in ascending order with the scan object for the MemStore at the end of the list.
-* When a `StoreFileScanner` object is constructed, it is associated with a `MultiVersionConsistencyControl` read point, which is the current `memstoreTS`, filtering out any new updates beyond the read point.
+* When a `StoreFileScanner` object is constructed, it is associated with a `MultiVersionConcurrencyControl` read point, which is the current `memstoreTS`, filtering out any new updates beyond the read point.
 
 [[hfile]]
 ==== StoreFile (HFile)