diff --git a/asterix-transactions/src/main/java/edu/uci/ics/asterix/transaction/management/opcallbacks/PrimaryIndexInstantSearchOperationCallback.java b/asterix-transactions/src/main/java/edu/uci/ics/asterix/transaction/management/opcallbacks/PrimaryIndexInstantSearchOperationCallback.java
new file mode 100644
index 0000000..718ea3f
--- /dev/null
+++ b/asterix-transactions/src/main/java/edu/uci/ics/asterix/transaction/management/opcallbacks/PrimaryIndexInstantSearchOperationCallback.java
@@ -0,0 +1,61 @@
+/*
+ * Copyright 2009-2012 by The Regents of the University of California
+ * Licensed 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 from
+ * 
+ *     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 edu.uci.ics.asterix.transaction.management.opcallbacks;
+
+import edu.uci.ics.asterix.transaction.management.exception.ACIDException;
+import edu.uci.ics.asterix.transaction.management.service.locking.ILockManager;
+import edu.uci.ics.asterix.transaction.management.service.transaction.TransactionContext;
+import edu.uci.ics.asterix.transaction.management.service.transaction.TransactionManagementConstants.LockManagerConstants.LockMode;
+import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
+import edu.uci.ics.hyracks.dataflow.common.data.accessors.ITupleReference;
+import edu.uci.ics.hyracks.storage.am.common.api.ISearchOperationCallback;
+
+/**
+ * Assumes LSM-BTrees as primary indexes. Implements try/locking and unlocking on primary keys.
+ */
+public class PrimaryIndexInstantSearchOperationCallback extends AbstractOperationCallback implements
+        ISearchOperationCallback {
+
+    public PrimaryIndexInstantSearchOperationCallback(int datasetId, int[] entityIdFields, ILockManager lockManager,
+            TransactionContext txnCtx) {
+        super(datasetId, entityIdFields, txnCtx, lockManager);
+    }
+
+    @Override
+    public boolean proceed(ITupleReference tuple) throws HyracksDataException {
+        int pkHash = computePrimaryKeyHashValue(tuple, primaryKeyFields);
+        try {
+            return lockManager.instantTryLock(datasetId, pkHash, LockMode.S, txnCtx);
+        } catch (ACIDException e) {
+            throw new HyracksDataException(e);
+        }
+    }
+
+    @Override
+    public void reconcile(ITupleReference tuple) throws HyracksDataException {
+        int pkHash = computePrimaryKeyHashValue(tuple, primaryKeyFields);
+        try {
+            lockManager.instantLock(datasetId, pkHash, LockMode.S, txnCtx);
+        } catch (ACIDException e) {
+            throw new HyracksDataException(e);
+        }
+    }
+
+    @Override
+    public void cancel(ITupleReference tuple) throws HyracksDataException {
+        //no op
+    }
+}
diff --git a/asterix-transactions/src/main/java/edu/uci/ics/asterix/transaction/management/service/locking/LockManager.java b/asterix-transactions/src/main/java/edu/uci/ics/asterix/transaction/management/service/locking/LockManager.java
index f7c101d..5687656 100644
--- a/asterix-transactions/src/main/java/edu/uci/ics/asterix/transaction/management/service/locking/LockManager.java
+++ b/asterix-transactions/src/main/java/edu/uci/ics/asterix/transaction/management/service/locking/LockManager.java
@@ -46,7 +46,7 @@
     public static final boolean IS_DEBUG_MODE = false;//true
 
     public static final boolean ALLOW_UPGRADE_FROM_ENTITY_TO_DATASET = true;
-    public static final int UPGRADE_TRHESHOLD_ENTITY_TO_DATASET = 100000;
+    public static final int UPGRADE_TRHESHOLD_ENTITY_TO_DATASET = 10000;
     private static final int DO_UPGRADE = 0;
     private static final int UPGRADED = 1;
     private static final int DONOT_UPGRADE = 2;