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diff --git a/src/de/lmu/ifi/dbs/elki/parallel/ParallelExecutor.java b/src/de/lmu/ifi/dbs/elki/parallel/ParallelExecutor.java
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+package de.lmu.ifi.dbs.elki.parallel;
+
+/*
+ This file is part of ELKI:
+ Environment for Developing KDD-Applications Supported by Index-Structures
+
+ Copyright (C) 2014
+ Ludwig-Maximilians-Universität München
+ Lehr- und Forschungseinheit für Datenbanksysteme
+ ELKI Development Team
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Affero General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License
+ along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.concurrent.Callable;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Future;
+
+import de.lmu.ifi.dbs.elki.database.ids.ArrayDBIDs;
+import de.lmu.ifi.dbs.elki.database.ids.DBIDArrayIter;
+import de.lmu.ifi.dbs.elki.database.ids.DBIDUtil;
+import de.lmu.ifi.dbs.elki.database.ids.DBIDs;
+import de.lmu.ifi.dbs.elki.parallel.processor.Processor;
+import de.lmu.ifi.dbs.elki.parallel.variables.SharedVariable;
+import de.lmu.ifi.dbs.elki.parallel.variables.SharedVariable.Instance;
+
+/**
+ * Class to run processors in parallel, on all available cores.
+ * 
+ * TODO: add progress
+ * 
+ * @author Erich Schubert
+ * 
+ * @apiviz.has BlockArrayRunner
+ * @apiviz.uses ParallelCore
+ */
+public class ParallelExecutor {
+  /**
+   * Run a task on all available CPUs.
+   * 
+   * @param ids IDs to process
+   * @param procs Processors to run
+   */
+  public static final void run(DBIDs ids, Processor... procs) {
+    // TODO: try different strategies anyway!
+    ArrayDBIDs aids = DBIDUtil.ensureArray(ids);
+    ParallelCore core = ParallelCore.getCore();
+    try {
+      final int size = aids.size();
+      core.connect();
+      int numparts = core.getParallelism();
+      // TODO: are there better heuristics for choosing this?
+      numparts = (size > numparts * numparts * 16) ? numparts * numparts - 1 : numparts;
+
+      final int blocksize = (size + (numparts - 1)) / numparts;
+      List<Future<ArrayDBIDs>> parts = new ArrayList<>(numparts);
+      for(int i = 0; i < numparts; i++) {
+        final int start = i * blocksize;
+        final int end = (start + blocksize < size) ? start + blocksize : size;
+        Callable<ArrayDBIDs> run = new BlockArrayRunner(aids, start, end, procs);
+        parts.add(core.submit(run));
+      }
+
+      for(Future<ArrayDBIDs> fut : parts) {
+        fut.get();
+      }
+    }
+    catch(ExecutionException e) {
+      throw new RuntimeException("Processor execution failed.", e);
+    }
+    catch(InterruptedException e) {
+      throw new RuntimeException("Parallel execution interrupted.");
+    }
+    finally {
+      core.disconnect();
+    }
+  }
+
+  /**
+   * Run for an array part, without step size.
+   * 
+   * @author Erich Schubert
+   * 
+   * @apiviz.uses Processor
+   */
+  protected static class BlockArrayRunner implements Callable<ArrayDBIDs>, Executor {
+    /**
+     * Array IDs to process
+     */
+    private ArrayDBIDs ids;
+
+    /**
+     * Start position
+     */
+    private int start;
+
+    /**
+     * End position
+     */
+    private int end;
+
+    /**
+     * The processor masters that own the instances.
+     */
+    private Processor[] procs;
+
+    /**
+     * Variables map.
+     */
+    private HashMap<SharedVariable<?>, SharedVariable.Instance<?>> variables = new HashMap<>();
+
+    /**
+     * Constructor.
+     * 
+     * @param ids IDs to process
+     * @param start Starting position
+     * @param end End position
+     * @param procs Processors to run
+     */
+    protected BlockArrayRunner(ArrayDBIDs ids, int start, int end, Processor[] procs) {
+      super();
+      this.ids = ids;
+      this.start = start;
+      this.end = end;
+      this.procs = procs;
+    }
+
+    @Override
+    public ArrayDBIDs call() {
+      Processor.Instance[] instances = new Processor.Instance[procs.length];
+      for(int i = 0; i < procs.length; i++) {
+        instances[i] = procs[i].instantiate(this);
+      }
+
+      DBIDArrayIter iter = ids.iter();
+      iter.seek(start);
+      for(int c = end - start; iter.valid() && c >= 0; iter.advance(), c--) {
+        for(int i = 0; i < instances.length; i++) {
+          instances[i].map(iter);
+        }
+      }
+      for(int i = 0; i < instances.length; i++) {
+        procs[i].cleanup(instances[i]);
+      }
+      return ids;
+    }
+
+    @Override
+    public <I extends Instance<?>> I getInstance(SharedVariable<I> parent) {
+      @SuppressWarnings("unchecked")
+      I inst = (I) variables.get(parent);
+      if(inst == null) {
+        inst = parent.instantiate();
+        variables.put(parent, inst);
+      }
+      return inst;
+    }
+  }
+}