HBASE-27732 NPE in TestBasicWALEntryStreamFSHLog.testEOFExceptionInOldWALsDirectory

Author: Apache9

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

@@ -298,27 +298,34 @@ public abstract class AbstractFSWAL<W extends WriterBase> implements WAL {
   final Comparator<Path> LOG_NAME_COMPARATOR =
     (o1, o2) -> Long.compare(getFileNumFromFileName(o1), getFileNumFromFileName(o2));
 
-  private static final class WalProps {
+  private static final class WALProps {
 
     /**
      * Map the encoded region name to the highest sequence id.
      * <p/>
      * Contains all the regions it has an entry for.
      */
-    public final Map<byte[], Long> encodedName2HighestSequenceId;
+    final Map<byte[], Long> encodedName2HighestSequenceId;
 
     /**
      * The log file size. Notice that the size may not be accurate if we do asynchronous close in
      * sub classes.
      */
-    public final long logSize;
+    final long logSize;
 
     /**
      * The nanoTime of the log rolling, used to determine the time interval that has passed since.
      */
-    public final long rollTimeNs;
+    final long rollTimeNs;
 
-    public WalProps(Map<byte[], Long> encodedName2HighestSequenceId, long logSize) {
+    /**
+     * If we do asynchronous close in sub classes, it is possible that when adding WALProps to the
+     * rolled map, the file is not closed yet, so in cleanOldLogs we should not archive this file,
+     * for safety.
+     */
+    volatile boolean closed = false;
+
+    public WALProps(Map<byte[], Long> encodedName2HighestSequenceId, long logSize) {
       this.encodedName2HighestSequenceId = encodedName2HighestSequenceId;
       this.logSize = logSize;
       this.rollTimeNs = System.nanoTime();
@@ -329,7 +336,7 @@ public WalProps(Map<byte[], Long> encodedName2HighestSequenceId, long logSize) {
    * Map of WAL log file to properties. The map is sorted by the log file creation timestamp
    * (contained in the log file name).
    */
-  protected ConcurrentNavigableMap<Path, WalProps> walFile2Props =
+  protected final ConcurrentNavigableMap<Path, WALProps> walFile2Props =
     new ConcurrentSkipListMap<>(LOG_NAME_COMPARATOR);
 
   /**
@@ -348,6 +355,9 @@ public WalProps(Map<byte[], Long> encodedName2HighestSequenceId, long logSize) {
 
   protected final AtomicBoolean rollRequested = new AtomicBoolean(false);
 
+  protected final ExecutorService closeExecutor = Executors.newCachedThreadPool(
+    new ThreadFactoryBuilder().setDaemon(true).setNameFormat("Close-WAL-Writer-%d").build());
+
   // Run in caller if we get reject execution exception, to avoid aborting region server when we get
   // reject execution exception. Usually this should not happen but let's make it more robust.
   private final ExecutorService logArchiveExecutor =
@@ -697,7 +707,7 @@ Map<byte[], List<byte[]>> findRegionsToForceFlush() throws IOException {
     Map<byte[], List<byte[]>> regions = null;
     int logCount = getNumRolledLogFiles();
     if (logCount > this.maxLogs && logCount > 0) {
-      Map.Entry<Path, WalProps> firstWALEntry = this.walFile2Props.firstEntry();
+      Map.Entry<Path, WALProps> firstWALEntry = this.walFile2Props.firstEntry();
       regions =
         this.sequenceIdAccounting.findLower(firstWALEntry.getValue().encodedName2HighestSequenceId);
     }
@@ -720,17 +730,34 @@ Map<byte[], List<byte[]>> findRegionsToForceFlush() throws IOException {
     return regions;
   }
 
+  /**
+   * Mark this WAL file as closed and call cleanOldLogs to see if we can archive this file.
+   */
+  protected final void markClosedAndClean(Path path) {
+    WALProps props = walFile2Props.get(path);
+    // typically this should not be null, but if there is no big issue if it is already null, so
+    // let's make the code more robust
+    if (props != null) {
+      props.closed = true;
+      cleanOldLogs();
+    }
+  }
+
   /**
    * Archive old logs. A WAL is eligible for archiving if all its WALEdits have been flushed.
    */
-  private void cleanOldLogs() throws IOException {
+  private void cleanOldLogs() {
     List<Pair<Path, Long>> logsToArchive = null;
     long now = System.nanoTime();
     boolean mayLogTooOld = nextLogTooOldNs <= now;
     ArrayList<byte[]> regionsBlockingWal = null;
     // For each log file, look at its Map of regions to highest sequence id; if all sequence ids
     // are older than what is currently in memory, the WAL can be GC'd.
-    for (Map.Entry<Path, WalProps> e : this.walFile2Props.entrySet()) {
+    for (Map.Entry<Path, WALProps> e : this.walFile2Props.entrySet()) {
+      if (!e.getValue().closed) {
+        LOG.debug("{} is not closed yet, will try archiving it next time", e.getKey());
+        continue;
+      }
       Path log = e.getKey();
       ArrayList<byte[]> regionsBlockingThisWal = null;
       long ageNs = now - e.getValue().rollTimeNs;
@@ -834,7 +861,7 @@ protected final void logRollAndSetupWalProps(Path oldPath, Path newPath, long ol
     String newPathString = newPath != null ? CommonFSUtils.getPath(newPath) : null;
     if (oldPath != null) {
       this.walFile2Props.put(oldPath,
-        new WalProps(this.sequenceIdAccounting.resetHighest(), oldFileLen));
+        new WALProps(this.sequenceIdAccounting.resetHighest(), oldFileLen));
       this.totalLogSize.addAndGet(oldFileLen);
       LOG.info("Rolled WAL {} with entries={}, filesize={}; new WAL {}",
         CommonFSUtils.getPath(oldPath), oldNumEntries, StringUtils.byteDesc(oldFileLen),

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

@@ -35,7 +35,6 @@
 import java.util.SortedSet;
 import java.util.TreeSet;
 import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
 import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
@@ -179,9 +178,6 @@ public class AsyncFSWAL extends AbstractFSWAL<AsyncWriter> {
 
   private final long batchSize;
 
-  private final ExecutorService closeExecutor = Executors.newCachedThreadPool(
-    new ThreadFactoryBuilder().setDaemon(true).setNameFormat("Close-WAL-Writer-%d").build());
-
   private volatile AsyncFSOutput fsOut;
 
   private final Deque<FSWALEntry> toWriteAppends = new ArrayDeque<>();
@@ -778,32 +774,35 @@ private void waitForSafePoint() {
     }
   }
 
-  protected final long closeWriter(AsyncWriter writer, Path path) {
-    if (writer != null) {
-      inflightWALClosures.put(path.getName(), writer);
-      long fileLength = writer.getLength();
-      closeExecutor.execute(() -> {
-        try {
-          writer.close();
-        } catch (IOException e) {
-          LOG.warn("close old writer failed", e);
-        } finally {
-          inflightWALClosures.remove(path.getName());
-        }
-      });
-      return fileLength;
-    } else {
-      return 0L;
-    }
+  private void closeWriter(AsyncWriter writer, Path path) {
+    inflightWALClosures.put(path.getName(), writer);
+    closeExecutor.execute(() -> {
+      try {
+        writer.close();
+      } catch (IOException e) {
+        LOG.warn("close old writer failed", e);
+      } finally {
+        // call this even if the above close fails, as there is no other chance we can set closed to
+        // true, it will not cause big problems.
+        markClosedAndClean(path);
+        inflightWALClosures.remove(path.getName());
+      }
+    });
   }
 
   @Override
   protected void doReplaceWriter(Path oldPath, Path newPath, AsyncWriter nextWriter)
     throws IOException {
     Preconditions.checkNotNull(nextWriter);
     waitForSafePoint();
-    long oldFileLen = closeWriter(this.writer, oldPath);
-    logRollAndSetupWalProps(oldPath, newPath, oldFileLen);
+    if (writer != null) {
+      long oldFileLen = writer.getLength();
+      logRollAndSetupWalProps(oldPath, newPath, oldFileLen);
+      closeWriter(writer, oldPath);
+    } else {
+      logRollAndSetupWalProps(oldPath, newPath, 0);
+    }
+
     this.writer = nextWriter;
     if (nextWriter instanceof AsyncProtobufLogWriter) {
       this.fsOut = ((AsyncProtobufLogWriter) nextWriter).getOutput();

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

@@ -36,8 +36,6 @@
 import java.util.List;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
 import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
@@ -169,8 +167,6 @@ public class FSHLog extends AbstractFSWAL<Writer> {
   private final AtomicInteger closeErrorCount = new AtomicInteger();
 
   private final int waitOnShutdownInSeconds;
-  private final ExecutorService closeExecutor = Executors.newCachedThreadPool(
-    new ThreadFactoryBuilder().setDaemon(true).setNameFormat("Close-WAL-Writer-%d").build());
 
   /**
    * Exception handler to pass the disruptor ringbuffer. Same as native implementation only it logs
@@ -377,10 +373,10 @@ protected void doReplaceWriter(Path oldPath, Path newPath, Writer nextWriter) th
         LOG.warn(
           "Failed sync-before-close but no outstanding appends; closing WAL" + e.getMessage());
       }
-      long oldFileLen = 0L;
       // It is at the safe point. Swap out writer from under the blocked writer thread.
       if (this.writer != null) {
-        oldFileLen = this.writer.getLength();
+        long oldFileLen = this.writer.getLength();
+        logRollAndSetupWalProps(oldPath, newPath, oldFileLen);
         // In case of having unflushed entries or we already reached the
         // closeErrorsTolerated count, call the closeWriter inline rather than in async
         // way so that in case of an IOE we will throw it back and abort RS.
@@ -393,12 +389,20 @@ protected void doReplaceWriter(Path oldPath, Path newPath, Writer nextWriter) th
             try {
               closeWriter(localWriter, oldPath, false);
             } catch (IOException e) {
-              // We will never reach here.
+              LOG.warn("close old writer failed", e);
+            } finally {
+              // call this even if the above close fails, as there is no other chance we can set
+              // closed to
+              // true, it will not cause big problems.
+              markClosedAndClean(oldPath);
+              inflightWALClosures.remove(oldPath.getName());
             }
           });
         }
+      } else {
+        logRollAndSetupWalProps(oldPath, newPath, 0);
       }
-      logRollAndSetupWalProps(oldPath, newPath, oldFileLen);
+
       this.writer = nextWriter;
       if (nextWriter != null && nextWriter instanceof ProtobufLogWriter) {
         this.hdfs_out = ((ProtobufLogWriter) nextWriter).getStream();
@@ -453,8 +457,6 @@ private void closeWriter(Writer writer, Path path, boolean syncCloseCall) throws
       }
       LOG.warn("Riding over failed WAL close of " + path
         + "; THIS FILE WAS NOT CLOSED BUT ALL EDITS SYNCED SO SHOULD BE OK", ioe);
-    } finally {
-      inflightWALClosures.remove(path.getName());
     }
   }
 

hbase-server/src/main/java/org/apache/hadoop/hbase/wal/AbstractFSWALProvider.java

@@ -415,10 +415,11 @@ public static ServerName getServerNameFromWALDirectoryName(Path logFile) {
       serverName = ServerName.parseServerName(logDirName);
     } catch (IllegalArgumentException | IllegalStateException ex) {
       serverName = null;
-      LOG.warn("Cannot parse a server name from path=" + logFile + "; " + ex.getMessage());
+      LOG.warn("Cannot parse a server name from path={}", logFile, ex);
     }
     if (serverName != null && serverName.getStartCode() < 0) {
-      LOG.warn("Invalid log file path=" + logFile);
+      LOG.warn("Invalid log file path={}, start code {} is less than 0", logFile,
+        serverName.getStartCode());
       serverName = null;
     }
     return serverName;
@@ -483,6 +484,11 @@ public static Path findArchivedLog(Path path, Configuration conf) throws IOExcep
     }
 
     ServerName serverName = getServerNameFromWALDirectoryName(path);
+    if (serverName == null) {
+      LOG.warn("Can not extract server name from path {}, "
+        + "give up searching the separated old log dir", path);
+      return null;
+    }
     // Try finding the log in separate old log dir
     oldLogDir = new Path(walRootDir, new StringBuilder(HConstants.HREGION_OLDLOGDIR_NAME)
       .append(Path.SEPARATOR).append(serverName.getServerName()).toString());