Index: oak-core/pom.xml
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-core/pom.xml	(date 1427834483000)
+++ oak-core/pom.xml	(date 1427877717000)
@@ -348,5 +348,10 @@
       <classifier>tests</classifier>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>commons-lang</groupId>
+      <artifactId>commons-lang</artifactId>
+      <scope>test</scope>
+    </dependency>
   </dependencies>
 </project>
Index: oak-core/src/test/java/org/apache/jackrabbit/oak/plugins/segment/SegmentCompactionIT.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-core/src/test/java/org/apache/jackrabbit/oak/plugins/segment/SegmentCompactionIT.java	(date 1427877717000)
+++ oak-core/src/test/java/org/apache/jackrabbit/oak/plugins/segment/SegmentCompactionIT.java	(date 1427877717000)
@@ -0,0 +1,171 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.apache.jackrabbit.oak.plugins.segment;
+
+import static org.apache.commons.io.FileUtils.deleteDirectory;
+import static org.apache.commons.lang.RandomStringUtils.randomAlphabetic;
+import static org.apache.jackrabbit.oak.plugins.segment.compaction.CompactionStrategy.CleanupType.CLEAN_OLD;
+import static org.apache.jackrabbit.oak.plugins.segment.compaction.CompactionStrategy.MEMORY_THRESHOLD_DEFAULT;
+import static org.slf4j.helpers.MessageFormatter.arrayFormat;
+import static org.slf4j.helpers.MessageFormatter.format;
+
+import java.io.ByteArrayInputStream;
+import java.io.File;
+import java.io.IOException;
+import java.util.Random;
+import java.util.concurrent.Callable;
+
+import javax.annotation.Nonnull;
+
+import com.google.common.collect.Iterables;
+import org.apache.jackrabbit.oak.api.Blob;
+import org.apache.jackrabbit.oak.api.CommitFailedException;
+import org.apache.jackrabbit.oak.plugins.segment.compaction.CompactionStrategy;
+import org.apache.jackrabbit.oak.plugins.segment.file.FileStore;
+import org.apache.jackrabbit.oak.spi.commit.CommitInfo;
+import org.apache.jackrabbit.oak.spi.commit.EmptyHook;
+import org.apache.jackrabbit.oak.spi.gc.GCMonitor;
+import org.apache.jackrabbit.oak.spi.state.NodeBuilder;
+import org.apache.jackrabbit.oak.spi.state.NodeStore;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class SegmentCompactionIT {
+    private static final Logger LOG = LoggerFactory.getLogger(SegmentCompactionIT.class);
+
+    private final Random rnd = new Random();
+
+    private File directory;
+
+    @Before
+    public void setUp() throws IOException {
+        directory = File.createTempFile(getClass().getSimpleName(), "dir", new File("target"));
+        directory.delete();
+        directory.mkdir();
+    }
+
+    @After
+    public void cleanDir() {
+        try {
+            deleteDirectory(directory);
+        } catch (IOException e) {
+            LOG.error("Error cleaning directory", e);
+        }
+    }
+
+    private volatile boolean compact = true;
+
+    private final GCMonitor gcMonitor = new GCMonitor() {
+        @Override
+        public void info(String message, Object... arguments) {
+            System.out.println(arrayFormat(message, arguments).getMessage());
+        }
+
+        @Override
+        public void warn(String message, Object... arguments) {
+            System.out.println(arrayFormat(message, arguments).getMessage());
+        }
+
+        @Override
+        public void error(String message, Exception exception) {
+            System.out.println(format(message, exception).getMessage());
+        }
+
+        @Override
+        public void skipped(String reason, Object... arguments) {
+            compact = true;
+            System.out.println(arrayFormat(reason, arguments).getMessage());
+        }
+
+        @Override
+        public void compacted() { }
+
+        @Override
+        public void cleaned(long reclaimedSize, long currentSize) {
+            compact = true;
+        }
+    };
+
+    @Test
+    public void run() throws IOException, CommitFailedException, InterruptedException {
+        FileStore fileStore = FileStore.newFileStore(directory).withGCMonitor(gcMonitor).create();
+        try {
+            final SegmentNodeStore nodeStore = new SegmentNodeStore(fileStore);
+            fileStore.setCompactionStrategy(new CompactionStrategy(false, false, CLEAN_OLD, 5000, MEMORY_THRESHOLD_DEFAULT) {
+                @Override
+                public boolean compacted(@Nonnull Callable<Boolean> setHead)
+                        throws Exception {
+                    return nodeStore.locked(setHead);
+                }
+            });
+
+            while (true) {
+                NodeBuilder root = nodeStore.getRoot().builder();
+                while (rnd.nextInt(100) != 0) {
+                    modify(nodeStore, root);
+                }
+                nodeStore.merge(root, EmptyHook.INSTANCE, CommitInfo.EMPTY);
+
+                if (compact) {
+                    compact = false;
+                    fileStore.maybeCompact(true);
+                }
+            }
+        } finally {
+            fileStore.close();
+        }
+    }
+
+    private void modify(NodeStore nodeStore, NodeBuilder nodeBuilder) throws IOException {
+        int k = rnd.nextInt(100);
+        if (k < 10) {
+            if (!nodeBuilder.remove()) {
+                descent(nodeStore, nodeBuilder);
+            }
+        } else if (k < 40)  {
+            nodeBuilder.setChildNode("N" + rnd.nextInt(1000));
+        } else if (k < 80) {
+            nodeBuilder.setProperty("P" + rnd.nextInt(1000), randomAlphabetic(rnd.nextInt(10000)));
+        } else if (k < 90) {
+            nodeBuilder.setProperty("B" + rnd.nextInt(1000), createBlob(nodeStore, rnd.nextInt(1000000)));
+        } else {
+            descent(nodeStore, nodeBuilder);
+        }
+    }
+
+    private void descent(NodeStore nodeStore, NodeBuilder nodeBuilder) throws IOException {
+        long count = nodeBuilder.getChildNodeCount(Long.MAX_VALUE);
+        if (count > 0) {
+            int c = rnd.nextInt((int) count);
+            String name = Iterables.get(nodeBuilder.getChildNodeNames(), c);
+            modify(nodeStore, nodeBuilder.getChildNode(name));
+        }
+    }
+
+    private static Blob createBlob(NodeStore nodeStore, int size) throws IOException {
+        byte[] data = new byte[size];
+        new Random().nextBytes(data);
+        return nodeStore.createBlob(new ByteArrayInputStream(data));
+    }
+
+}
Index: oak-parent/pom.xml
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-parent/pom.xml	(date 1427834483000)
+++ oak-parent/pom.xml	(date 1427877717000)
@@ -435,6 +435,11 @@
           </exclusion>
         </exclusions>
       </dependency>
+      <dependency>
+        <groupId>commons-lang</groupId>
+        <artifactId>commons-lang</artifactId>
+        <version>2.6</version>
+      </dependency>
     </dependencies>
   </dependencyManagement>