HADOOP-11648. Set DomainSocketWatcher thread name explicitly. Contributed by Liang Xie.

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -647,6 +647,9 @@ Release 2.7.0 - UNRELEASED
     HADOOP-11658. Externalize io.compression.codecs property.
     (Kai Zheng via aajisaka)
 
+    HADOOP-11648. Set DomainSocketWatcher thread name explicitly.
+    (Liang Xie via ozawa)
+
   OPTIMIZATIONS
 
     HADOOP-11323. WritableComparator#compare keeps reference to byte array.

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/net/unix/DomainSocketWatcher.java

@@ -238,7 +238,8 @@ public final class DomainSocketWatcher implements Closeable {
    */
   private boolean kicked = false;
 
-  public DomainSocketWatcher(int interruptCheckPeriodMs) throws IOException {
+  public DomainSocketWatcher(int interruptCheckPeriodMs, String src)
+      throws IOException {
     if (loadingFailureReason != null) {
       throw new UnsupportedOperationException(loadingFailureReason);
     }
@@ -246,8 +247,9 @@ public final class DomainSocketWatcher implements Closeable {
     this.interruptCheckPeriodMs = interruptCheckPeriodMs;
     notificationSockets = DomainSocket.socketpair();
     watcherThread.setDaemon(true);
-    watcherThread.setUncaughtExceptionHandler(
-        new Thread.UncaughtExceptionHandler() {
+    watcherThread.setName(src + " DomainSocketWatcher");
+    watcherThread
+        .setUncaughtExceptionHandler(new Thread.UncaughtExceptionHandler() {
           @Override
           public void uncaughtException(Thread thread, Throwable t) {
             LOG.error(thread + " terminating on unexpected exception", t);

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/net/unix/TestDomainSocketWatcher.java

@@ -195,7 +195,7 @@ public class TestDomainSocketWatcher {
   private DomainSocketWatcher newDomainSocketWatcher(int interruptCheckPeriodMs)
       throws Exception {
     DomainSocketWatcher watcher = new DomainSocketWatcher(
-        interruptCheckPeriodMs);
+        interruptCheckPeriodMs, getClass().getSimpleName());
     watcher.watcherThread.setUncaughtExceptionHandler(
         new Thread.UncaughtExceptionHandler() {
           @Override

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

@@ -712,6 +712,9 @@ Release 2.7.0 - UNRELEASED
     HDFS-7746. Add a test randomly mixing append, truncate and snapshot
     operations. (szetszwo)
 
+    HADOOP-11648. Set DomainSocketWatcher thread name explicitly.
+    (Liang Xie via ozawa)
+
   OPTIMIZATIONS
 
     HDFS-7454. Reduce memory footprint for AclEntries in NameNode.

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/ShortCircuitRegistry.java

@@ -176,7 +176,7 @@ public class ShortCircuitRegistry {
       if (dswLoadingFailure != null) {
         throw new IOException(dswLoadingFailure);
       }
-      watcher = new DomainSocketWatcher(interruptCheck);
+      watcher = new DomainSocketWatcher(interruptCheck, "datanode");
       enabled = true;
       if (LOG.isDebugEnabled()) {
         LOG.debug("created new ShortCircuitRegistry with interruptCheck=" +

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/DfsClientShmManager.java

@@ -412,7 +412,8 @@ public class DfsClientShmManager implements Closeable {
   private final DomainSocketWatcher domainSocketWatcher;
   
   DfsClientShmManager(int interruptCheckPeriodMs) throws IOException {
-    this.domainSocketWatcher = new DomainSocketWatcher(interruptCheckPeriodMs);
+    this.domainSocketWatcher = new DomainSocketWatcher(interruptCheckPeriodMs,
+        "client");
   }
   
   public Slot allocSlot(DatanodeInfo datanode, DomainPeer peer,