HDFS-9141. Thread leak in Datanode#refreshVolumes. (Uma Maheswara Rao G via yliu)

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

@@ -1106,6 +1106,9 @@ Release 2.8.0 - UNRELEASED
     HDFS-9092. Nfs silently drops overlapping write requests and causes data
     copying to fail. (Yongjun Zhang)
 
+    HDFS-9141. Thread leak in Datanode#refreshVolumes. (Uma Maheswara Rao G
+    via yliu)
+
 Release 2.7.2 - UNRELEASED
 
   INCOMPATIBLE CHANGES

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

@@ -25,9 +25,7 @@ import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_DATA_DIR_PERMISS
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_DATA_DIR_PERMISSION_KEY;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_DIRECTORYSCAN_INTERVAL_DEFAULT;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_DIRECTORYSCAN_INTERVAL_KEY;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_DNS_INTERFACE_DEFAULT;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_DNS_INTERFACE_KEY;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_DNS_NAMESERVER_DEFAULT;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_DNS_NAMESERVER_KEY;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_HANDLER_COUNT_DEFAULT;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_HANDLER_COUNT_KEY;
@@ -611,7 +609,7 @@ public class DataNode extends ReconfigurableBase
   private synchronized void refreshVolumes(String newVolumes) throws IOException {
     Configuration conf = getConf();
     conf.set(DFS_DATANODE_DATA_DIR_KEY, newVolumes);
-
+    ExecutorService service = null;
     int numOldDataDirs = dataDirs.size();
     ChangedVolumes changedVolumes = parseChangedVolumes(newVolumes);
     StringBuilder errorMessageBuilder = new StringBuilder();
@@ -634,8 +632,8 @@ public class DataNode extends ReconfigurableBase
         for (BPOfferService bpos : blockPoolManager.getAllNamenodeThreads()) {
           nsInfos.add(bpos.getNamespaceInfo());
         }
-        ExecutorService service = Executors.newFixedThreadPool(
-            changedVolumes.newLocations.size());
+        service = Executors
+            .newFixedThreadPool(changedVolumes.newLocations.size());
         List<Future<IOException>> exceptions = Lists.newArrayList();
         for (final StorageLocation location : changedVolumes.newLocations) {
           exceptions.add(service.submit(new Callable<IOException>() {
@@ -685,6 +683,9 @@ public class DataNode extends ReconfigurableBase
         throw new IOException(errorMessageBuilder.toString());
       }
     } finally {
+      if (service != null) {
+        service.shutdown();
+      }
       conf.set(DFS_DATANODE_DATA_DIR_KEY,
           Joiner.on(",").join(effectiveVolumes));
       dataDirs = getStorageLocations(conf);