diff --git a/ftk/src/ftk.h b/ftk/src/ftk.h
index a2e1518..0ca93c6 100644
--- a/ftk/src/ftk.h
+++ b/ftk/src/ftk.h
@@ -3926,6 +3926,7 @@
 			
 		virtual RCODE FLMAPI resize(
 			FLMUINT 					uiNumBytes,
+			FLMBOOL					bPreallocate,
 			FLMUINT *				puiActualSize = NULL) = 0;
 	
 		virtual void FLMAPI incrementTotalBytesAllocated(
@@ -3963,9 +3964,9 @@
 			FLMUINT *				puiTotalBytesAllocated) = 0;
 	
 		virtual void * FLMAPI allocCell(
-			IF_Relocator *			pRelocator = NULL,
-			void *					pvInitialData = NULL,
-			FLMUINT					uiDataSize = 0) = 0;
+			IF_Relocator *			pRelocator,
+			void *					pvInitialData,
+			FLMUINT					uiDataSize) = 0;
 	
 		virtual void * FLMAPI allocCell(
 			IF_Relocator *			pRelocator,
diff --git a/ftk/src/ftkmem.cpp b/ftk/src/ftkmem.cpp
index fac9761..0847ed6 100644
--- a/ftk/src/ftkmem.cpp
+++ b/ftk/src/ftkmem.cpp
@@ -198,6 +198,7 @@ public:
 		
 	RCODE FLMAPI resize(
 		FLMUINT 				uiNumBytes,
+		FLMBOOL				bPreallocate,
 		FLMUINT *			puiActualSize = NULL);
 
 	void FLMAPI incrementTotalBytesAllocated(
@@ -2277,7 +2278,7 @@ RCODE FLMAPI F_SlabManager::setup(
 	
 	if( uiPreallocSize)
 	{
-		if( RC_BAD( rc = resize( uiPreallocSize, NULL)))
+		if( RC_BAD( rc = resize( uiPreallocSize, TRUE, NULL)))
 		{
 			goto Exit;
 		}
@@ -2293,6 +2294,7 @@ Desc:
 ****************************************************************************/
 RCODE FLMAPI F_SlabManager::resize(
 	FLMUINT 			uiNumBytes,
+	FLMBOOL			bPreallocate,
 	FLMUINT *		puiActualSize)
 {
 	RCODE				rc = NE_FLM_OK;
@@ -2350,7 +2352,7 @@ RCODE FLMAPI F_SlabManager::resize(
 			m_uiTotalBytesAllocated -= m_uiSlabSize;
 		}
 	}
-	else
+	else if( bPreallocate)
 	{
 		// Allocate the required number of slabs
 		
@@ -2392,8 +2394,15 @@ RCODE FLMAPI F_SlabManager::resize(
 	{
 		*puiActualSize = m_uiTotalSlabs * m_uiSlabSize;
 	}
-
-	m_uiPreallocSlabs = m_uiTotalSlabs;
+	
+	if( bPreallocate)
+	{
+		m_uiPreallocSlabs = m_uiTotalSlabs;
+	}
+	else
+	{
+		m_uiPreallocSlabs = 0;
+	}
 	
 Exit:
 
diff --git a/ftk/src/ftkunix.cpp b/ftk/src/ftkunix.cpp
index cf72959..5d7c1fd 100644
--- a/ftk/src/ftkunix.cpp
+++ b/ftk/src/ftkunix.cpp
@@ -449,7 +449,7 @@ Exit:
 Desc:	Truncate the file to the indicated size
 ******************************************************************************/
 RCODE FLMAPI F_FileHdl::truncate(
-	FLMUINT64		uiNew64Size)
+	FLMUINT64		ui64NewSize)
 {
 	RCODE				rc = NE_FLM_OK;
 	FLMUINT64		ui64CurrentSize;
@@ -466,7 +466,7 @@ RCODE FLMAPI F_FileHdl::truncate(
 		goto Exit;
 	}
 
-	if( ftruncate( m_fd, ui64Size) == -1)
+	if( ftruncate( m_fd, ui64NewSize) == -1)
 	{
 		rc = f_mapPlatformError( errno, NE_FLM_TRUNCATING_FILE);
 		goto Exit;
@@ -675,7 +675,6 @@ RCODE F_FileHdl::lowLevelWrite(
 	F_FileAsyncClient *	pAsyncClient = NULL;
 	FLMBOOL					bWaitForWrite = FALSE;
 	FLMBYTE *				pucExtendBuffer = NULL;
-	FLMUINT					uiTotalBytesToExtend;
 	
 	if( pIOBuffer && pvBuffer && pvBuffer != pIOBuffer->getBufferPtr())
 	{
@@ -694,6 +693,9 @@ RCODE F_FileHdl::lowLevelWrite(
 	
 	if( m_bDoDirectIO && !m_numAsyncPending && m_uiExtendSize)
 	{
+		FLMUINT64		ui64CurrFileSize;
+		FLMUINT			uiTotalBytesToExtend;
+		
 		if( RC_BAD( rc = getPreWriteExtendSize( ui64WriteOffset, uiBytesToWrite,
 			&ui64CurrFileSize, &uiTotalBytesToExtend)))
 		{