Index: oak-segment/src/main/java/org/apache/jackrabbit/oak/plugins/segment/SegmentWriter.java
===================================================================
--- oak-segment/src/main/java/org/apache/jackrabbit/oak/plugins/segment/SegmentWriter.java	(revision 1731857)
+++ oak-segment/src/main/java/org/apache/jackrabbit/oak/plugins/segment/SegmentWriter.java	(working copy)
@@ -109,7 +109,7 @@
      * Cache of recently stored template records, used to avoid storing
      * duplicates of frequently occurring data.
      */
-    final Map<Template, RecordId> templateCache = newItemsCache(TPL_RECORDS_CACHE_SIZE);
+    final Map<String, RecordId> templateCache = newItemsCache(TPL_RECORDS_CACHE_SIZE);
 
     private static final <T> Map<T, RecordId> newItemsCache(final int size) {
         final boolean disabled = size <= 0;
@@ -589,10 +589,10 @@
         }
     }
 
-    public RecordId writeTemplate(Template template) throws IOException {
+    private RecordId writeTemplate(Template template) throws IOException {
         checkNotNull(template);
 
-        RecordId id = templateCache.get(template);
+        RecordId id = templateCache.get(template.hash());
         if (id != null) {
             return id; // shortcut if the same template was recently stored
         }
@@ -663,7 +663,7 @@
         RecordId tid = writeRecord(newTemplateWriter(ids, propertyNames,
                 propertyTypes, head, primaryId, mixinIds, childNameId,
                 propNamesId, version));
-        templateCache.put(template, tid);
+        templateCache.put(template.hash(), tid);
         return tid;
     }
 
Index: oak-segment/src/main/java/org/apache/jackrabbit/oak/plugins/segment/Template.java
===================================================================
--- oak-segment/src/main/java/org/apache/jackrabbit/oak/plugins/segment/Template.java	(revision 1731857)
+++ oak-segment/src/main/java/org/apache/jackrabbit/oak/plugins/segment/Template.java	(working copy)
@@ -32,8 +32,14 @@
 import javax.annotation.Nonnull;
 
 import com.google.common.base.Objects;
+import com.google.common.base.Supplier;
+import com.google.common.base.Suppliers;
 import com.google.common.collect.Lists;
+import com.google.common.hash.Funnel;
+import com.google.common.hash.Hashing;
+import com.google.common.hash.PrimitiveSink;
 
+import org.apache.commons.io.Charsets;
 import org.apache.jackrabbit.oak.api.PropertyState;
 import org.apache.jackrabbit.oak.api.Type;
 import org.apache.jackrabbit.oak.plugins.memory.MemoryChildNodeEntry;
@@ -48,6 +54,55 @@
  */
 public class Template {
 
+    private static final Funnel<Template> templateFunnel = new Funnel<Template>() {
+
+        private static final long serialVersionUID = -8151688031296826818L;
+
+        @Override
+        public void funnel(Template t, PrimitiveSink into) {
+            if (t.getPrimaryType() != null) {
+                into.putString(t.getPrimaryType().getValue(Type.STRING),
+                        Charsets.UTF_8);
+            }
+            if (t.getMixinTypes() != null) {
+                into.putShort((short) 0);
+            } else {
+                into.putShort((short) 1);
+            }
+            if (t.getMixinTypes() != null) {
+                if (t.getMixinTypes().isArray()) {
+                    for (String m : t.getMixinTypes().getValue(Type.STRINGS)) {
+                        into.putString(m, Charsets.UTF_8);
+                    }
+                } else {
+                    into.putString(t.getMixinTypes().getValue(Type.STRING),
+                            Charsets.UTF_8);
+                }
+            }
+            if (t.getPropertyTemplates() != null) {
+                for (PropertyTemplate pt : t.getPropertyTemplates()) {
+                    into.putString(pt.getName(), Charsets.UTF_8);
+                    into.putString(pt.getType().toString(), Charsets.UTF_8);
+                }
+            }
+            into.putShort(t.getTemplateType());
+            if (t.getChildName() != null) {
+                into.putString(t.getChildName(), Charsets.UTF_8);
+            }
+        }
+    };
+
+    static final Supplier<String> newTemplateHasher(final Template t) {
+        return new Supplier<String>() {
+
+            @Override
+            public String get() {
+                return Hashing.md5().newHasher().putObject(t, templateFunnel).hash()
+                        .toString();
+            }
+        };
+    }
+
     static final short ZERO_CHILD_NODES_TYPE = 0;
 
     static final short SINGLE_CHILD_NODE_TYPE = 1;
@@ -87,6 +142,12 @@
     @CheckForNull
     private final String childName;
 
+    /**
+     * Used for deduplication of Template object in the {@link SegmentWriter#templateCache}
+     */
+    private final Supplier<String> hasher = Suppliers
+            .memoize(newTemplateHasher(this));
+
     Template(PropertyState primaryType, PropertyState mixinTypes,
             PropertyTemplate[] properties, String childName) {
         this.primaryType = primaryType;
@@ -284,6 +345,10 @@
         }
     }
 
+    public String hash() {
+        return hasher.get();
+    }
+
     //------------------------------------------------------------< Object >--
 
     @Override
Index: oak-segment/src/test/java/org/apache/jackrabbit/oak/plugins/segment/TemplateTest.java
===================================================================
--- oak-segment/src/test/java/org/apache/jackrabbit/oak/plugins/segment/TemplateTest.java	(revision 1731857)
+++ oak-segment/src/test/java/org/apache/jackrabbit/oak/plugins/segment/TemplateTest.java	(working copy)
@@ -17,16 +17,14 @@
 package org.apache.jackrabbit.oak.plugins.segment;
 
 import static org.apache.jackrabbit.oak.plugins.memory.PropertyStates.createProperty;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
 
 import java.io.IOException;
 import java.util.ArrayList;
 
 import org.apache.jackrabbit.oak.api.PropertyState;
 import org.apache.jackrabbit.oak.api.Type;
-
-import static org.junit.Assert.*;
-
-import org.junit.Assert;
 import org.junit.Test;
 
 public class TemplateTest {
@@ -42,6 +40,7 @@
         Template t1 = new Template(primary, mixin, properties, null);
 
         assertNotEquals(t0.hashCode(), t1.hashCode());
+        assertNotEquals(t0.hash(), t1.hash());
     }
 
     @Test
@@ -57,6 +56,7 @@
         Template t1 = new Template(primary, mixin, properties, childNode);
 
         assertNotEquals(t0.hashCode(), t1.hashCode());
+        assertNotEquals(t0.hash(), t1.hash());
     }
 
     @Test
@@ -76,5 +76,6 @@
         Template t1 = new Template(primary, mixin, pt1, childNode);
 
         assertEquals(t0, t1);
+        assertEquals(t0.hash(), t1.hash());
     }
 }