diff --git a/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/AbstractDiskLSMComponent.java b/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/AbstractDiskLSMComponent.java
index 5765f71..55ba584 100644
--- a/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/AbstractDiskLSMComponent.java
+++ b/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/AbstractDiskLSMComponent.java
@@ -30,7 +30,9 @@
 
     @Override
     public boolean threadEnter(LSMOperationType opType, boolean isMutableComponent) {
-        assert state != ComponentState.INACTIVE;
+        if (state == ComponentState.INACTIVE) {
+            throw new IllegalStateException("Trying to enter an inactive disk component");
+        }
 
         switch (opType) {
             case FORCE_MODIFICATION:
@@ -75,7 +77,10 @@
             default:
                 throw new UnsupportedOperationException("Unsupported operation " + opType);
         }
-        assert readerCount > -1;
+        
+        if (readerCount <= -1) {
+            throw new IllegalStateException("Invalid LSM disk component readerCount: " + readerCount);
+        }
     }
 
     @Override
diff --git a/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/AbstractLSMIndex.java b/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/AbstractLSMIndex.java
index ee03570..7717a2b 100644
--- a/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/AbstractLSMIndex.java
+++ b/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/AbstractLSMIndex.java
@@ -248,19 +248,23 @@
     public String toString() {
         return "LSMIndex [" + fileManager.getBaseDir() + "]";
     }
-    
+
     @Override
     public boolean hasMemoryComponents() {
         return true;
     }
-    
+
     @Override
     public boolean isCurrentMutableComponentEmpty() throws HyracksDataException {
         //check if the current memory component has been modified
         return !((AbstractMemoryLSMComponent) memoryComponents.get(currentMutableComponentId.get())).isModified();
     }
-    
-    public void makeCurrentMutableComponentUnWritable() throws HyracksDataException {
-        ((AbstractMemoryLSMComponent) memoryComponents.get(currentMutableComponentId.get())).setState(ComponentState.READABLE_UNWRITABLE);
+
+    public void setCurrentMutableComponentState(ComponentState componentState) {
+        ((AbstractMemoryLSMComponent) memoryComponents.get(currentMutableComponentId.get())).setState(componentState);
+    }
+
+    public ComponentState getCurrentMutableComponentState() {
+        return ((AbstractMemoryLSMComponent) memoryComponents.get(currentMutableComponentId.get())).getState();
     }
 }
diff --git a/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/AbstractMemoryLSMComponent.java b/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/AbstractMemoryLSMComponent.java
index b86e98f..76694bb 100644
--- a/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/AbstractMemoryLSMComponent.java
+++ b/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/AbstractMemoryLSMComponent.java
@@ -92,7 +92,10 @@
                 break;
             case FLUSH:
                 if (state == ComponentState.READABLE_WRITABLE || state == ComponentState.READABLE_UNWRITABLE) {
-                    assert writerCount == 0;
+
+                    if (writerCount != 0) {
+                        throw new IllegalStateException("Trying to flush when writerCount != 0");
+                    }
                     state = ComponentState.READABLE_UNWRITABLE_FLUSHING;
                     readerCount++;
                 } else {
@@ -131,7 +134,9 @@
                 }
                 break;
             case FLUSH:
-                assert state == ComponentState.READABLE_UNWRITABLE_FLUSHING;
+                if (state != ComponentState.READABLE_UNWRITABLE_FLUSHING) {
+                    throw new IllegalStateException("Flush sees an illegal LSM memory compoenent state: " + state);
+                }
                 readerCount--;
                 if (readerCount == 0) {
                     state = ComponentState.INACTIVE;
@@ -142,7 +147,10 @@
             default:
                 throw new UnsupportedOperationException("Unsupported operation " + opType);
         }
-        assert readerCount > -1 && writerCount > -1;
+
+        if (readerCount <= -1 || writerCount <= -1) {
+            throw new IllegalStateException("Invalid reader or writer count " + readerCount + " - " + writerCount);
+        }
     }
 
     public boolean isReadable() {
@@ -161,7 +169,7 @@
     public ComponentState getState() {
         return state;
     }
-    
+
     public void setState(ComponentState state) {
         this.state = state;
     }
diff --git a/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/LSMHarness.java b/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/LSMHarness.java
index d26854f..9f66f63 100644
--- a/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/LSMHarness.java
+++ b/hyracks/hyracks-storage-am-lsm-common/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/common/impls/LSMHarness.java
@@ -27,6 +27,7 @@
 import edu.uci.ics.hyracks.storage.am.common.api.IndexException;
 import edu.uci.ics.hyracks.storage.am.common.ophelpers.IndexOperation;
 import edu.uci.ics.hyracks.storage.am.lsm.common.api.ILSMComponent;
+import edu.uci.ics.hyracks.storage.am.lsm.common.api.ILSMComponent.ComponentState;
 import edu.uci.ics.hyracks.storage.am.lsm.common.api.ILSMComponent.LSMComponentType;
 import edu.uci.ics.hyracks.storage.am.lsm.common.api.ILSMHarness;
 import edu.uci.ics.hyracks.storage.am.lsm.common.api.ILSMIOOperation;
@@ -61,7 +62,10 @@
                     case FLUSH:
                         ILSMComponent flushingComponent = ctx.getComponentHolder().get(0);
                         if (!((AbstractMemoryLSMComponent) flushingComponent).isModified()) {
-                            // The mutable component has not been modified by any writer. There is nothing to flush.
+                            //The mutable component has not been modified by any writer. There is nothing to flush.
+                            //since the component is empty, set its state back to READABLE_WRITABLE
+                            ((AbstractLSMIndex) lsmIndex)
+                                    .setCurrentMutableComponentState(ComponentState.READABLE_WRITABLE);
                             return false;
                         }
                         break;
@@ -104,6 +108,9 @@
                 numEntered++;
             }
             entranceSuccessful = numEntered == components.size();
+        } catch (Throwable e) {
+            e.printStackTrace();
+            throw e;
         } finally {
             if (!entranceSuccessful) {
                 int i = 0;
@@ -197,8 +204,13 @@
                     default:
                         break;
                 }
+            } catch (Throwable e) {
+                e.printStackTrace();
+                throw e;
+
             } finally {
-                if (failedOperation && (opType == LSMOperationType.MODIFICATION || opType == LSMOperationType.FORCE_MODIFICATION)) {
+                if (failedOperation
+                        && (opType == LSMOperationType.MODIFICATION || opType == LSMOperationType.FORCE_MODIFICATION)) {
                     //When the operation failed, completeOperation() method must be called 
                     //in order to decrement active operation count which was incremented in beforeOperation() method.
                     opTracker.completeOperation(lsmIndex, opType, ctx.getSearchOperationCallback(),
@@ -292,6 +304,10 @@
             newComponent = lsmIndex.flush(operation);
             operation.getCallback().afterOperation(LSMOperationType.FLUSH, null, newComponent);
             lsmIndex.markAsValid(newComponent);
+        } catch (Throwable e) {
+            e.printStackTrace();
+            throw e;
+
         } finally {
             exitComponents(ctx, LSMOperationType.FLUSH, newComponent, false);
             operation.getCallback().afterFinalize(LSMOperationType.FLUSH, newComponent);
@@ -337,6 +353,10 @@
             newComponent = lsmIndex.merge(operation);
             operation.getCallback().afterOperation(LSMOperationType.MERGE, ctx.getComponentHolder(), newComponent);
             lsmIndex.markAsValid(newComponent);
+        } catch (Throwable e) {
+            e.printStackTrace();
+            throw e;
+
         } finally {
             exitComponents(ctx, LSMOperationType.MERGE, newComponent, false);
             operation.getCallback().afterFinalize(LSMOperationType.MERGE, newComponent);
@@ -349,8 +369,10 @@
     @Override
     public void addBulkLoadedComponent(ILSMComponent c) throws HyracksDataException, IndexException {
         lsmIndex.markAsValid(c);
-        lsmIndex.addComponent(c);
-        mergePolicy.diskComponentAdded(lsmIndex, false);
+        synchronized (opTracker) {
+            lsmIndex.addComponent(c);
+            mergePolicy.diskComponentAdded(lsmIndex, false);
+        }
     }
 
     @Override