HDFS-2738. FSEditLog.selectinputStreams is reading through in-progress streams even when non-in-progress are requested. Contributed by Aaron T. Myers

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/HDFS-1623@1229931 13f79535-47bb-0310-9956-ffa450edef68

hadoop-hdfs-project/hadoop-hdfs/CHANGES.HDFS-1623.txt

@@ -101,3 +101,5 @@ HDFS-2773. Reading edit logs from an earlier version should not leave blocks in
 HDFS-2775. Fix TestStandbyCheckpoints.testBothNodesInStandbyState failing intermittently. (todd)
 
 HDFS-2766. Test for case where standby partially reads log and then performs checkpoint. (atm)
+
+HDFS-2738. FSEditLog.selectinputStreams is reading through in-progress streams even when non-in-progress are requested. (atm)

hadoop-hdfs-project/hadoop-hdfs/src/contrib/bkjournal/src/main/java/org/apache/hadoop/contrib/bkjournal/BookKeeperJournalManager.java

@@ -312,8 +312,10 @@ public class BookKeeperJournalManager implements JournalManager {
     }
   }
 
+  // TODO(HA): Handle inProgressOk
   @Override
-  public EditLogInputStream getInputStream(long fromTxnId) throws IOException {
+  public EditLogInputStream getInputStream(long fromTxnId, boolean inProgressOk)
+      throws IOException {
     for (EditLogLedgerMetadata l : getLedgerList()) {
       if (l.getFirstTxId() == fromTxnId) {
         try {
@@ -329,8 +331,10 @@ public class BookKeeperJournalManager implements JournalManager {
     throw new IOException("No ledger for fromTxnId " + fromTxnId + " found.");
   }
 
+  // TODO(HA): Handle inProgressOk
   @Override
-  public long getNumberOfTransactions(long fromTxnId) throws IOException {
+  public long getNumberOfTransactions(long fromTxnId, boolean inProgressOk)
+      throws IOException {
     long count = 0;
     long expectedStart = 0;
     for (EditLogLedgerMetadata l : getLedgerList()) {

hadoop-hdfs-project/hadoop-hdfs/src/contrib/bkjournal/src/test/java/org/apache/hadoop/contrib/bkjournal/TestBookKeeperJournalManager.java

@@ -195,7 +195,7 @@ public class TestBookKeeperJournalManager {
     out.close();
     bkjm.finalizeLogSegment(1, 100);
 
-    long numTrans = bkjm.getNumberOfTransactions(1);
+    long numTrans = bkjm.getNumberOfTransactions(1, true);
     assertEquals(100, numTrans);
   }
 
@@ -218,17 +218,17 @@ public class TestBookKeeperJournalManager {
     }
     zkc.delete(bkjm.finalizedLedgerZNode(DEFAULT_SEGMENT_SIZE+1, DEFAULT_SEGMENT_SIZE*2), -1);
     
-    long numTrans = bkjm.getNumberOfTransactions(1);
+    long numTrans = bkjm.getNumberOfTransactions(1, true);
     assertEquals(DEFAULT_SEGMENT_SIZE, numTrans);
     
     try {
-      numTrans = bkjm.getNumberOfTransactions(DEFAULT_SEGMENT_SIZE+1);
+      numTrans = bkjm.getNumberOfTransactions(DEFAULT_SEGMENT_SIZE+1, true);
       fail("Should have thrown corruption exception by this point");
     } catch (JournalManager.CorruptionException ce) {
       // if we get here, everything is going good
     }
 
-    numTrans = bkjm.getNumberOfTransactions((DEFAULT_SEGMENT_SIZE*2)+1);
+    numTrans = bkjm.getNumberOfTransactions((DEFAULT_SEGMENT_SIZE*2)+1, true);
     assertEquals(DEFAULT_SEGMENT_SIZE, numTrans);
   }
 
@@ -262,7 +262,7 @@ public class TestBookKeeperJournalManager {
     out.abort();
     out.close();
     
-    long numTrans = bkjm.getNumberOfTransactions(1);
+    long numTrans = bkjm.getNumberOfTransactions(1, true);
     assertEquals((txid-1), numTrans);
   }
 
@@ -357,7 +357,7 @@ public class TestBookKeeperJournalManager {
     bkjm.finalizeLogSegment(1, numTransactions);
 
      
-    EditLogInputStream in = bkjm.getInputStream(1);
+    EditLogInputStream in = bkjm.getInputStream(1, true);
     try {
       assertEquals(numTransactions, 
                    FSEditLogTestUtil.countTransactionsInStream(in));

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/BackupJournalManager.java

@@ -58,7 +58,7 @@ class BackupJournalManager implements JournalManager {
   }
 
   @Override
-  public long getNumberOfTransactions(long fromTxnId) 
+  public long getNumberOfTransactions(long fromTxnId, boolean inProgressOk)
       throws IOException, CorruptionException {
     // This JournalManager is never used for input. Therefore it cannot
     // return any transactions
@@ -66,7 +66,8 @@ class BackupJournalManager implements JournalManager {
   }
   
   @Override
-  public EditLogInputStream getInputStream(long fromTxnId) throws IOException {
+  public EditLogInputStream getInputStream(long fromTxnId, boolean inProgressOk)
+      throws IOException {
     // This JournalManager is never used for input. Therefore it cannot
     // return any transactions
     throw new IOException("Unsupported operation");

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSEditLog.java

@@ -252,7 +252,7 @@ public class FSEditLog  {
     long segmentTxId = getLastWrittenTxId() + 1;
     // Safety check: we should never start a segment if there are
     // newer txids readable.
-    EditLogInputStream s = journalSet.getInputStream(segmentTxId);
+    EditLogInputStream s = journalSet.getInputStream(segmentTxId, true);
     try {
       Preconditions.checkState(s == null,
           "Cannot start writing at txid %s when there is a stream " +
@@ -1071,19 +1071,19 @@ public class FSEditLog  {
   public Collection<EditLogInputStream> selectInputStreams(long fromTxId,
       long toAtLeastTxId, boolean inProgressOk) throws IOException {
     List<EditLogInputStream> streams = new ArrayList<EditLogInputStream>();
-    EditLogInputStream stream = journalSet.getInputStream(fromTxId);
+    EditLogInputStream stream = journalSet.getInputStream(fromTxId, inProgressOk);
     while (stream != null) {
-      if (inProgressOk || !stream.isInProgress()) {
       streams.add(stream);
-      }
       // We're now looking for a higher range, so reset the fromTxId
       fromTxId = stream.getLastTxId() + 1;
-      stream = journalSet.getInputStream(fromTxId);
+      stream = journalSet.getInputStream(fromTxId, inProgressOk);
     }
+    
     if (fromTxId <= toAtLeastTxId) {
       closeAllStreams(streams);
-      throw new IOException("No non-corrupt logs for txid " 
+      throw new IOException(String.format("Gap in transactions. Expected to "
-                            + fromTxId);
+          + "be able to read up until at least txid %d but unable to find any "
+          + "edit logs containing txid %d", toAtLeastTxId, fromTxId));
     }
     return streams;
   }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSImage.java

@@ -585,9 +585,12 @@ public class FSImage implements Closeable {
 
     if (LayoutVersion.supports(Feature.TXID_BASED_LAYOUT, 
                                getLayoutVersion())) {
+      // If we're open for write, we're either non-HA or we're the active NN, so
+      // we better be able to load all the edits. If we're the standby NN, it's
+      // OK to not be able to read all of edits right now.
+      long toAtLeastTxId = editLog.isOpenForWrite() ? inspector.getMaxSeenTxId() : 0;
       editStreams = editLog.selectInputStreams(imageFile.getCheckpointTxId() + 1,
-                                               inspector.getMaxSeenTxId(),
+          toAtLeastTxId, false);
-                                               false);
     } else {
       editStreams = FSImagePreTransactionalStorageInspector
         .getEditLogStreams(storage);

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FileJournalManager.java

@@ -31,6 +31,7 @@ import java.util.regex.Pattern;
 import org.apache.hadoop.fs.FileUtil;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants;
 import org.apache.hadoop.hdfs.server.common.Storage.StorageDirectory;
+import org.apache.hadoop.hdfs.server.namenode.JournalManager.CorruptionException;
 import org.apache.hadoop.hdfs.server.namenode.NNStorageRetentionManager.StoragePurger;
 import org.apache.hadoop.hdfs.server.namenode.FSEditLogLoader.EditLogValidation;
 import org.apache.hadoop.hdfs.server.namenode.NNStorage.NameNodeFile;
@@ -192,10 +193,13 @@ class FileJournalManager implements JournalManager {
   }
 
   @Override
-  synchronized public EditLogInputStream getInputStream(long fromTxId)
+  synchronized public EditLogInputStream getInputStream(long fromTxId,
-      throws IOException {
+      boolean inProgressOk) throws IOException {
     for (EditLogFile elf : getLogFiles(fromTxId)) {
       if (elf.containsTxId(fromTxId)) {
+        if (!inProgressOk && elf.isInProgress()) {
+          continue;
+        }
         if (elf.isInProgress()) {
           elf.validateLog();
         }
@@ -219,7 +223,7 @@ class FileJournalManager implements JournalManager {
   }
 
   @Override
-  public long getNumberOfTransactions(long fromTxId) 
+  public long getNumberOfTransactions(long fromTxId, boolean inProgressOk)
       throws IOException, CorruptionException {
     long numTxns = 0L;
     
@@ -232,6 +236,10 @@ class FileJournalManager implements JournalManager {
             + fromTxId + " - " + (elf.getFirstTxId() - 1));
         break;
       } else if (elf.containsTxId(fromTxId)) {
+        if (!inProgressOk && elf.isInProgress()) {
+          break;
+        }
+        
         if (elf.isInProgress()) {
           elf.validateLog();
         } 
@@ -253,7 +261,7 @@ class FileJournalManager implements JournalManager {
                 + " txns from " + fromTxId);
     }
 
-    long max = findMaxTransaction();
+    long max = findMaxTransaction(inProgressOk);
     
     // fromTxId should be greater than max, as it points to the next 
     // transaction we should expect to find. If it is less than or equal
@@ -276,7 +284,7 @@ class FileJournalManager implements JournalManager {
     
     // make sure journal is aware of max seen transaction before moving corrupt 
     // files aside
-    findMaxTransaction();
+    findMaxTransaction(true);
 
     for (EditLogFile elf : allLogFiles) {
       if (elf.getFile().equals(currentInProgress)) {
@@ -318,9 +326,13 @@ class FileJournalManager implements JournalManager {
    * tranaction id in the case that it was the maximum transaction in
    * the journal.
    */
-  private long findMaxTransaction()
+  private long findMaxTransaction(boolean inProgressOk)
       throws IOException {
     for (EditLogFile elf : getLogFiles(0)) {
+      if (elf.isInProgress() && !inProgressOk) {
+        continue;
+      }
+      
       if (elf.isInProgress()) {
         maxSeenTransaction = Math.max(elf.getFirstTxId(), maxSeenTransaction);
         elf.validateLog();

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/JournalManager.java

@@ -48,20 +48,23 @@ public interface JournalManager extends Closeable {
    /**
    * Get the input stream starting with fromTxnId from this journal manager
    * @param fromTxnId the first transaction id we want to read
+   * @param inProgressOk whether or not in-progress streams should be returned
    * @return the stream starting with transaction fromTxnId
    * @throws IOException if a stream cannot be found.
    */
-  EditLogInputStream getInputStream(long fromTxnId) throws IOException;
+  EditLogInputStream getInputStream(long fromTxnId, boolean inProgressOk)
+    throws IOException;
 
   /**
    * Get the number of transaction contiguously available from fromTxnId.
    *
    * @param fromTxnId Transaction id to count from
+   * @param inProgressOk whether or not in-progress streams should be counted
    * @return The number of transactions available from fromTxnId
    * @throws IOException if the journal cannot be read.
    * @throws CorruptionException if there is a gap in the journal at fromTxnId.
    */
-  long getNumberOfTransactions(long fromTxnId) 
+  long getNumberOfTransactions(long fromTxnId, boolean inProgressOk)
       throws IOException, CorruptionException;
 
   /**

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/JournalSet.java

@@ -198,7 +198,8 @@ public class JournalSet implements JournalManager {
    *         or null if no more exist
    */
   @Override
-  public EditLogInputStream getInputStream(long fromTxnId) throws IOException {
+  public EditLogInputStream getInputStream(long fromTxnId, boolean inProgressOk)
+      throws IOException {
     JournalManager bestjm = null;
     long bestjmNumTxns = 0;
     CorruptionException corruption = null;
@@ -209,7 +210,8 @@ public class JournalSet implements JournalManager {
       JournalManager candidate = jas.getManager();
       long candidateNumTxns = 0;
       try {
-        candidateNumTxns = candidate.getNumberOfTransactions(fromTxnId);
+        candidateNumTxns = candidate.getNumberOfTransactions(fromTxnId,
+            inProgressOk);
       } catch (CorruptionException ce) {
         corruption = ce;
       } catch (IOException ioe) {
@@ -232,18 +234,20 @@ public class JournalSet implements JournalManager {
         return null;
       }
     }
-    return bestjm.getInputStream(fromTxnId);
+    return bestjm.getInputStream(fromTxnId, inProgressOk);
   }
   
   @Override
-  public long getNumberOfTransactions(long fromTxnId) throws IOException {
+  public long getNumberOfTransactions(long fromTxnId, boolean inProgressOk)
+      throws IOException {
     long num = 0;
     for (JournalAndStream jas: journals) {
       if (jas.isDisabled()) {
         LOG.info("Skipping jas " + jas + " since it's disabled");
         continue;
       } else {
-        long newNum = jas.getManager().getNumberOfTransactions(fromTxnId);
+        long newNum = jas.getManager().getNumberOfTransactions(fromTxnId,
+            inProgressOk);
         if (newNum > num) {
           num = newNum;
         }

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestEditLog.java

@@ -936,11 +936,11 @@ public class TestEditLog extends TestCase {
    * 
    * @param editUris directories to create edit logs in
    * @param numrolls number of times to roll the edit log during setup
+   * @param closeOnFinish whether to close the edit log after setup
    * @param abortAtRolls Specifications for when to fail, see AbortSpec
    */
   public static NNStorage setupEdits(List<URI> editUris, int numrolls,
-                                     AbortSpec... abortAtRolls)
+      boolean closeOnFinish, AbortSpec... abortAtRolls) throws IOException {
-      throws IOException {
     List<AbortSpec> aborts = new ArrayList<AbortSpec>(Arrays.asList(abortAtRolls));
     NNStorage storage = new NNStorage(new Configuration(),
                                       Collections.<URI>emptyList(),
@@ -979,16 +979,34 @@ public class TestEditLog extends TestCase {
       }
       editlog.logSync();
     }
+    
+    if (closeOnFinish) {
       editlog.close();
+    }
 
     FSImageTestUtil.logStorageContents(LOG, storage);
     return storage;
   }
     
+  /**
+   * Set up directories for tests. 
+   *
+   * Each rolled file is 10 txns long. 
+   * A failed file is 2 txns long.
+   * 
+   * @param editUris directories to create edit logs in
+   * @param numrolls number of times to roll the edit log during setup
+   * @param abortAtRolls Specifications for when to fail, see AbortSpec
+   */
+  public static NNStorage setupEdits(List<URI> editUris, int numrolls, 
+      AbortSpec... abortAtRolls) throws IOException {
+    return setupEdits(editUris, numrolls, true, abortAtRolls);
+  }
+
   /** 
    * Test loading an editlog which has had both its storage fail
    * on alternating rolls. Two edit log directories are created.
-   * The first on fails on odd rolls, the second on even. Test
+   * The first one fails on odd rolls, the second on even. Test
    * that we are able to load the entire editlog regardless.
    */
   @Test

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFileJournalManager.java

@@ -60,7 +60,7 @@ public class TestFileJournalManager {
     long numJournals = 0;
     for (StorageDirectory sd : storage.dirIterable(NameNodeDirType.EDITS)) {
       FileJournalManager jm = new FileJournalManager(sd);
-      assertEquals(6*TXNS_PER_ROLL, jm.getNumberOfTransactions(1));
+      assertEquals(6*TXNS_PER_ROLL, jm.getNumberOfTransactions(1, true));
       numJournals++;
     }
     assertEquals(3, numJournals);
@@ -81,7 +81,7 @@ public class TestFileJournalManager {
 
     FileJournalManager jm = new FileJournalManager(sd);
     assertEquals(5*TXNS_PER_ROLL + TXNS_PER_FAIL, 
-                 jm.getNumberOfTransactions(1));
+                 jm.getNumberOfTransactions(1, true));
   }
 
   /**
@@ -103,15 +103,16 @@ public class TestFileJournalManager {
     Iterator<StorageDirectory> dirs = storage.dirIterator(NameNodeDirType.EDITS);
     StorageDirectory sd = dirs.next();
     FileJournalManager jm = new FileJournalManager(sd);
-    assertEquals(6*TXNS_PER_ROLL, jm.getNumberOfTransactions(1));
+    assertEquals(6*TXNS_PER_ROLL, jm.getNumberOfTransactions(1, true));
     
     sd = dirs.next();
     jm = new FileJournalManager(sd);
-    assertEquals(5*TXNS_PER_ROLL + TXNS_PER_FAIL, jm.getNumberOfTransactions(1));
+    assertEquals(5*TXNS_PER_ROLL + TXNS_PER_FAIL, jm.getNumberOfTransactions(1,
+        true));
 
     sd = dirs.next();
     jm = new FileJournalManager(sd);
-    assertEquals(6*TXNS_PER_ROLL, jm.getNumberOfTransactions(1));
+    assertEquals(6*TXNS_PER_ROLL, jm.getNumberOfTransactions(1, true));
   }
 
   /** 
@@ -135,15 +136,18 @@ public class TestFileJournalManager {
     Iterator<StorageDirectory> dirs = storage.dirIterator(NameNodeDirType.EDITS);
     StorageDirectory sd = dirs.next();
     FileJournalManager jm = new FileJournalManager(sd);
-    assertEquals(5*TXNS_PER_ROLL + TXNS_PER_FAIL, jm.getNumberOfTransactions(1));
+    assertEquals(5*TXNS_PER_ROLL + TXNS_PER_FAIL, jm.getNumberOfTransactions(1,
+        true));
     
     sd = dirs.next();
     jm = new FileJournalManager(sd);
-    assertEquals(5*TXNS_PER_ROLL + TXNS_PER_FAIL, jm.getNumberOfTransactions(1));
+    assertEquals(5*TXNS_PER_ROLL + TXNS_PER_FAIL, jm.getNumberOfTransactions(1,
+        true));
 
     sd = dirs.next();
     jm = new FileJournalManager(sd);
-    assertEquals(5*TXNS_PER_ROLL + TXNS_PER_FAIL, jm.getNumberOfTransactions(1));
+    assertEquals(5*TXNS_PER_ROLL + TXNS_PER_FAIL, jm.getNumberOfTransactions(1,
+        true));
   }
 
   /** 
@@ -174,15 +178,15 @@ public class TestFileJournalManager {
 
     FileJournalManager jm = new FileJournalManager(sd);
     long expectedTotalTxnCount = TXNS_PER_ROLL*10 + TXNS_PER_FAIL;
-    assertEquals(expectedTotalTxnCount, jm.getNumberOfTransactions(1));
+    assertEquals(expectedTotalTxnCount, jm.getNumberOfTransactions(1, true));
 
     long skippedTxns = (3*TXNS_PER_ROLL); // skip first 3 files
     long startingTxId = skippedTxns + 1; 
 
-    long numTransactionsToLoad = jm.getNumberOfTransactions(startingTxId);
+    long numTransactionsToLoad = jm.getNumberOfTransactions(startingTxId, true);
     long numLoaded = 0;
     while (numLoaded < numTransactionsToLoad) {
-      EditLogInputStream editIn = jm.getInputStream(startingTxId);
+      EditLogInputStream editIn = jm.getInputStream(startingTxId, true);
       FSEditLogLoader.EditLogValidation val = FSEditLogLoader.validateEditLog(editIn);
       long count = val.getNumTransactions();
 
@@ -212,7 +216,8 @@ public class TestFileJournalManager {
     // 10 rolls, so 11 rolled files, 110 txids total.
     final int TOTAL_TXIDS = 10 * 11;
     for (int txid = 1; txid <= TOTAL_TXIDS; txid++) {
-      assertEquals((TOTAL_TXIDS - txid) + 1, jm.getNumberOfTransactions(txid));
+      assertEquals((TOTAL_TXIDS - txid) + 1, jm.getNumberOfTransactions(txid,
+          true));
     }
   }
 
@@ -244,10 +249,10 @@ public class TestFileJournalManager {
     assertTrue(files[0].delete());
     
     FileJournalManager jm = new FileJournalManager(sd);
-    assertEquals(startGapTxId-1, jm.getNumberOfTransactions(1));
+    assertEquals(startGapTxId-1, jm.getNumberOfTransactions(1, true));
 
     try {
-      jm.getNumberOfTransactions(startGapTxId);
+      jm.getNumberOfTransactions(startGapTxId, true);
       fail("Should have thrown an exception by now");
     } catch (IOException ioe) {
       assertTrue(true);
@@ -255,7 +260,7 @@ public class TestFileJournalManager {
 
     // rolled 10 times so there should be 11 files.
     assertEquals(11*TXNS_PER_ROLL - endGapTxId, 
-                 jm.getNumberOfTransactions(endGapTxId+1));
+                 jm.getNumberOfTransactions(endGapTxId + 1, true));
   }
 
   /** 
@@ -282,7 +287,7 @@ public class TestFileJournalManager {
 
     FileJournalManager jm = new FileJournalManager(sd);
     assertEquals(10*TXNS_PER_ROLL+1, 
-                 jm.getNumberOfTransactions(1)); 
+                 jm.getNumberOfTransactions(1, true));
   }
 
   @Test
@@ -323,11 +328,37 @@ public class TestFileJournalManager {
     
     FileJournalManager jm = new FileJournalManager(sd);
     
-    EditLogInputStream elis = jm.getInputStream(5);
+    EditLogInputStream elis = jm.getInputStream(5, true);
     FSEditLogOp op = elis.readOp();
     assertEquals("read unexpected op", op.getTransactionId(), 5);
   }
 
+  /**
+   * Make sure that in-progress streams aren't counted if we don't ask for
+   * them.
+   */
+  @Test
+  public void testExcludeInProgressStreams() throws CorruptionException,
+      IOException {
+    File f = new File(TestEditLog.TEST_DIR + "/filejournaltest2");
+    
+    // Don't close the edit log once the files have been set up.
+    NNStorage storage = setupEdits(Collections.<URI>singletonList(f.toURI()), 
+                                   10, false);
+    StorageDirectory sd = storage.dirIterator(NameNodeDirType.EDITS).next();
+    
+    FileJournalManager jm = new FileJournalManager(sd);
+    
+    // If we exclude the in-progess stream, we should only have 100 tx.
+    assertEquals(100, jm.getNumberOfTransactions(1, false));
+    
+    EditLogInputStream elis = jm.getInputStream(90, false);
+    FSEditLogOp lastReadOp = null;
+    while ((lastReadOp = elis.readOp()) != null) {
+      assertTrue(lastReadOp.getTransactionId() <= 100);
+    }
+  }
+
   private static String getLogsAsString(
       FileJournalManager fjm, long firstTxId) throws IOException {
     return Joiner.on(",").join(fjm.getRemoteEditLogs(firstTxId));

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestGenericJournalConf.java

@@ -144,13 +144,13 @@ public class TestGenericJournalConf {
     }
 
     @Override
-    public EditLogInputStream getInputStream(long fromTxnId)
+    public EditLogInputStream getInputStream(long fromTxnId, boolean inProgressOk)
         throws IOException {
       return null;
     }
 
     @Override
-    public long getNumberOfTransactions(long fromTxnId)
+    public long getNumberOfTransactions(long fromTxnId, boolean inProgressOk)
         throws IOException {
       return 0;
     }