Fix testAllDatanodesReconfig UT failed

Author: lfxy

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

@@ -217,7 +217,7 @@ private static INodeDirectory createRoot(FSNamesystem namesystem) {
   // authorizeWithContext() API or not.
   private boolean useAuthorizationWithContextAPI = false;
 
-  private final int MAX_DIR_ITEMS = 64 * 100 * 1000;
+  private final int maxDirItems = 64 * 100 * 1000;
 
   public void setINodeAttributeProvider(
       @Nullable INodeAttributeProvider provider) {
@@ -401,9 +401,9 @@ public enum DirOp {
     // to 64MB. This means we can only store approximately 6.7 million entries
     // per directory, but let's use 6.4 million for some safety.
     Preconditions.checkArgument(
-        maxDirItems > 0 && maxDirItems <= MAX_DIR_ITEMS, "Cannot set "
+        maxDirItems > 0 && maxDirItems <= maxDirItems, "Cannot set "
             + DFSConfigKeys.DFS_NAMENODE_MAX_DIRECTORY_ITEMS_KEY
-            + " to a value less than 1 or greater than " + MAX_DIR_ITEMS);
+            + " to a value less than 1 or greater than " + maxDirItems);
 
     int threshold = conf.getInt(
         DFSConfigKeys.DFS_NAMENODE_NAME_CACHE_THRESHOLD_KEY,
@@ -583,9 +583,9 @@ String setProtectedDirectories(String protectedDirsString) {
 
   public void setMaxDirItems(int newVal) {
     com.google.common.base.Preconditions.checkArgument(
-        newVal > 0 && newVal <= MAX_DIR_ITEMS, "Cannot set "
+        newVal > 0 && newVal <= maxDirItems, "Cannot set "
             + DFSConfigKeys.DFS_NAMENODE_MAX_DIRECTORY_ITEMS_KEY
-            + " to a value less than 1 or greater than " + MAX_DIR_ITEMS);
+            + " to a value less than 1 or greater than " + maxDirItems);
     maxDirItems = newVal;
   }
 

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/tools/TestDFSAdmin.java

@@ -1252,6 +1252,7 @@ public void testAllDatanodesReconfig()
         any(Configuration.class))).thenReturn(changes);
 
     int result = admin.startReconfiguration("datanode", "livenodes");
+    Thread.sleep(1000);
     assertThat(result).isEqualTo(0);
     final List<String> outsForStartReconf = new ArrayList<>();
     final List<String> errsForStartReconf = new ArrayList<>();