diff -r e1e34b95279b openide.loaders/src/org/netbeans/modules/openide/loaders/DataNodeUtils.java
--- a/openide.loaders/src/org/netbeans/modules/openide/loaders/DataNodeUtils.java	Wed Sep 09 17:15:18 2015 +0000
+++ b/openide.loaders/src/org/netbeans/modules/openide/loaders/DataNodeUtils.java	Wed Sep 09 22:10:47 2015 +0200
@@ -37,6 +37,11 @@
  */
 package org.netbeans.modules.openide.loaders;
 
+import java.util.Map;
+import java.util.WeakHashMap;
+import org.openide.filesystems.FileObject;
+import org.openide.filesystems.FileStateInvalidException;
+import org.openide.filesystems.FileSystem;
 import org.openide.util.RequestProcessor;
 
 /** Currently allows to share RP for nodes used by different packages
@@ -46,11 +51,41 @@
  */
 public final class DataNodeUtils {
     private static final RequestProcessor RP = new RequestProcessor("Data System Nodes"); // NOI18N
-    
+
+    private static final Map<FileSystem, RequestProcessor> FS_2_RP
+            = new WeakHashMap<FileSystem, RequestProcessor>();
+
     private DataNodeUtils() {
     }
 
     public static RequestProcessor reqProcessor() {
         return RP;
     }
+
+    /**
+     * Get request processor for a file.
+     *
+     * @param fo Some FileObject.
+     * @return Request Processor (newly) assigned to the file's filesystem.
+     */
+    public static RequestProcessor reqProcessor(FileObject fo) {
+        if (fo == null) {
+            return RP;
+        }
+        FileSystem fs;
+        try {
+            fs = fo.getFileSystem();
+            synchronized (FS_2_RP) {
+                RequestProcessor rp = FS_2_RP.get(fs);
+                if (rp == null) {
+                    rp = new RequestProcessor("Data System Nodes for " //NOI18N
+                            + fs.getDisplayName());
+                    FS_2_RP.put(fs, rp);
+                }
+                return rp;
+            }
+        } catch (FileStateInvalidException ex) {
+            return RP;
+        }
+    }
 }
diff -r e1e34b95279b openide.loaders/src/org/openide/loaders/FolderChildren.java
--- a/openide.loaders/src/org/openide/loaders/FolderChildren.java	Wed Sep 09 17:15:18 2015 +0000
+++ b/openide.loaders/src/org/openide/loaders/FolderChildren.java	Wed Sep 09 22:10:47 2015 +0200
@@ -177,8 +177,13 @@
         class R implements Runnable {
             List<FolderChildrenPair> positioned = null;
             RefreshMode op;
+            Task prevTask = null;
             @Override
             public void run() {
+                if (prevTask != null) {
+                    prevTask.waitFinished();
+                    prevTask = null; // do not hold task chain indefinitely
+                }
                 if (op == RefreshMode.DEEP) {
                     positioned = getPositionedFolderChildrenPairs(); //#229746
                     op = RefreshMode.DEEP_LATER;
@@ -230,7 +235,10 @@
             run.run();
         } else {
             run.op = operation;
-            refTask = DataNodeUtils.reqProcessor().post(run);
+            synchronized (this) {
+                run.prevTask = refTask;
+                refTask = DataNodeUtils.reqProcessor(folder.getPrimaryFile()).post(run);
+            }
         }
     }