diff --git a/asterix-transactions/src/main/java/edu/uci/ics/asterix/transaction/management/opcallbacks/IndexOperationTracker.java b/asterix-transactions/src/main/java/edu/uci/ics/asterix/transaction/management/opcallbacks/IndexOperationTracker.java
index b2391ae..6713492 100644
--- a/asterix-transactions/src/main/java/edu/uci/ics/asterix/transaction/management/opcallbacks/IndexOperationTracker.java
+++ b/asterix-transactions/src/main/java/edu/uci/ics/asterix/transaction/management/opcallbacks/IndexOperationTracker.java
@@ -33,20 +33,24 @@
     private final ILSMIndex index;
     private final ILSMIndexAccessor accessor;
     private final ILSMIOOperationCallback ioOpCallback;
-    
+
     public IndexOperationTracker(ILSMIndex index, ILSMIOOperationCallbackFactory ioOpCallbackFactory) {
         this.index = index;
         accessor = (ILSMIndexAccessor) index.createAccessor(NoOpOperationCallback.INSTANCE,
                 NoOpOperationCallback.INSTANCE);
         ioOpCallback = ioOpCallbackFactory.createIOOperationCallback(this);
-    }     
+    }
 
     @Override
-    public synchronized void beforeOperation(ILSMIndexOperationContext opCtx) throws HyracksDataException {
+    public synchronized boolean beforeOperation(ILSMIndexOperationContext opCtx, boolean tryOperation)
+            throws HyracksDataException {
         // Wait for pending flushes to complete.
         // If flushFlag is set, then the flush is queued to occur by the last completing operation.
         // This operation should wait for that flush to occur before proceeding.
         if (index.getFlushController().getFlushStatus(index)) {
+            if (tryOperation) {
+                return false;
+            }
             try {
                 this.wait();
             } catch (InterruptedException e) {
@@ -54,10 +58,12 @@
             }
         }
         numActiveOperations++;
-        
+
         // Increment transactor-local active operations count.
         AbstractOperationCallback opCallback = getOperationCallback(opCtx);
         opCallback.incrementLocalNumActiveOperations();
+
+        return true;
     }
 
     @Override
@@ -76,14 +82,14 @@
         // Decrement transactor-local active operations count.
         AbstractOperationCallback opCallback = getOperationCallback(opCtx);
         opCallback.decrementLocalNumActiveOperations();
-        
+
         // If we need a flush, and this is the last completing operation, then schedule the flush.
         // Once the flush has completed notify all waiting operations.
         if (index.getFlushController().getFlushStatus(index) && numActiveOperations == 0) {
             index.getIOScheduler().scheduleOperation(accessor.createFlushOperation(ioOpCallback));
         }
     }
-    
+
     private AbstractOperationCallback getOperationCallback(ILSMIndexOperationContext opCtx) {
         IndexOperation op = opCtx.getOperation();
         if (op == IndexOperation.SEARCH || op == IndexOperation.DISKORDERSCAN) {
@@ -92,11 +98,11 @@
             return (AbstractOperationCallback) opCtx.getModificationCallback();
         }
     }
-    
+
     public long getLastLSN() {
         return lastLsn;
     }
-    
+
     public void setLastLSN(long lastLsn) {
         this.lastLsn = lastLsn;
     }