diff --git a/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/util/FileSystemWatcher.java b/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/util/FileSystemWatcher.java
index 258f194..ab1c424 100644
--- a/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/util/FileSystemWatcher.java
+++ b/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/util/FileSystemWatcher.java
@@ -34,7 +34,6 @@
 import java.util.Iterator;
 import java.util.LinkedList;
 import java.util.List;
-import java.util.concurrent.locks.ReentrantLock;
 
 import org.apache.asterix.common.exceptions.ErrorCode;
 import org.apache.asterix.common.exceptions.RuntimeDataException;
@@ -55,7 +54,6 @@
     private final boolean isFeed;
     private boolean done;
     private final LinkedList<Path> dirs;
-    private final ReentrantLock lock = new ReentrantLock();
 
     public FileSystemWatcher(List<Path> inputResources, String expression, boolean isFeed) throws HyracksDataException {
         this.isFeed = isFeed;
@@ -145,7 +143,7 @@
         return (WatchEvent<T>) event;
     }
 
-    private void handleEvents(WatchKey key) throws IOException {
+    private synchronized void handleEvents(WatchKey key) throws IOException {
         // get dir associated with the key
         Path dir = keys.get(key);
         if (dir == null) {
@@ -172,7 +170,7 @@
             Path name = ev.context();
             Path child = dir.resolve(name);
             // if directory is created then register it and its sub-directories
-            if ((kind == StandardWatchEventKinds.ENTRY_CREATE)) {
+            if (kind == StandardWatchEventKinds.ENTRY_CREATE) {
                 try {
                     if (Files.isDirectory(child, LinkOption.NOFOLLOW_LINKS)) {
                         register(child);
@@ -229,7 +227,7 @@
     }
 
     // take is blocking
-    public synchronized File take() throws IOException {
+    public File take() throws IOException {
         File next = poll();
         if (next != null) {
             return next;
@@ -238,36 +236,31 @@
             return null;
         }
         // No file was found, wait for the filesystem to push events
-        WatchKey key = null;
-        lock.lock();
-        try {
-            while (!it.hasNext()) {
-                try {
-                    key = watcher.take();
-                } catch (InterruptedException x) {
-                    if (LOGGER.isEnabledFor(Level.WARN)) {
-                        LOGGER.warn("Feed Closed");
-                    }
-                    if (watcher == null) {
-                        return null;
-                    }
-                    continue;
-                } catch (ClosedWatchServiceException e) {
-                    if (LOGGER.isEnabledFor(Level.WARN)) {
-                        LOGGER.warn("The watcher has exited");
-                    }
-                    if (watcher == null) {
-                        return null;
-                    }
-                    continue;
+        WatchKey key;
+        while (!it.hasNext()) {
+            try {
+                key = watcher.take();
+            } catch (InterruptedException x) {
+                if (LOGGER.isEnabledFor(Level.WARN)) {
+                    LOGGER.warn("Feed Closed");
                 }
-                handleEvents(key);
-                if (endOfEvents(key)) {
+                if (watcher == null) {
                     return null;
                 }
+                continue;
+            } catch (ClosedWatchServiceException e) {
+                if (LOGGER.isEnabledFor(Level.WARN)) {
+                    LOGGER.warn("The watcher has exited");
+                }
+                if (watcher == null) {
+                    return null;
+                }
+                continue;
             }
-        } finally {
-            lock.unlock();
+            handleEvents(key);
+            if (endOfEvents(key)) {
+                return null;
+            }
         }
         // files were found, re-create the iterator and move it one step
         return it.next();
diff --git a/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/util/LocalFileSystemUtils.java b/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/util/LocalFileSystemUtils.java
index f6046ef..2cb842b 100644
--- a/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/util/LocalFileSystemUtils.java
+++ b/asterixdb/asterix-external-data/src/main/java/org/apache/asterix/external/util/LocalFileSystemUtils.java
@@ -27,6 +27,7 @@
 import java.nio.file.SimpleFileVisitor;
 import java.nio.file.attribute.BasicFileAttributes;
 import java.util.LinkedList;
+import java.util.List;
 import java.util.regex.Pattern;
 
 import org.apache.asterix.common.exceptions.ErrorCode;
@@ -34,7 +35,7 @@
 
 public class LocalFileSystemUtils {
 
-    public static void traverse(final LinkedList<File> files, File root, final String expression,
+    public static void traverse(final List<File> files, File root, final String expression,
             final LinkedList<Path> dirs) throws IOException {
         final Path path = root.toPath();
         if (!Files.exists(path)) {
@@ -70,8 +71,17 @@
         });
     }
 
-    public static void validateAndAdd(Path path, String expression, LinkedList<File> files) {
-        if (expression == null || Pattern.matches(expression, path.toString())) {
+    private static boolean fileNotExistsInList(List<File> files, Path path) {
+        for (File file : files) {
+            if (file.getPath().equals(path.toString())) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    public static void validateAndAdd(Path path, String expression, List<File> files) {
+        if ((expression == null || Pattern.matches(expression, path.toString())) && fileNotExistsInList(files, path)) {
             files.add(new File(path.toString()));
         }
     }
diff --git a/asterixdb/asterix-metadata/src/main/java/org/apache/asterix/metadata/feeds/FeedMetadataUtil.java b/asterixdb/asterix-metadata/src/main/java/org/apache/asterix/metadata/feeds/FeedMetadataUtil.java
index 584aead..b54c9e6 100644
--- a/asterixdb/asterix-metadata/src/main/java/org/apache/asterix/metadata/feeds/FeedMetadataUtil.java
+++ b/asterixdb/asterix-metadata/src/main/java/org/apache/asterix/metadata/feeds/FeedMetadataUtil.java
@@ -103,7 +103,6 @@
             ARecordType adapterOutputType = getOutputType(feed, configuration, ExternalDataConstants.KEY_TYPE_NAME);
             ARecordType metaType = getOutputType(feed, configuration, ExternalDataConstants.KEY_META_TYPE_NAME);
             ExternalDataUtils.prepareFeed(configuration, feed.getDataverseName(), feed.getFeedName());
-            ExternalDataUtils.prepareFeed(configuration, feed.getDataverseName(), feed.getFeedName());
             // Get adapter from metadata dataset <Metadata dataverse>
             DatasourceAdapter adapterEntity = MetadataManager.INSTANCE.getAdapter(mdTxnCtx,
                     MetadataConstants.METADATA_DATAVERSE_NAME, adapterName);