diff --git a/test/check_merge.cpp b/test/check_merge.cpp
index 4a124bc..690cc5f 100644
--- a/test/check_merge.cpp
+++ b/test/check_merge.cpp
@@ -55,14 +55,13 @@ void insertProbeIter(size_t NUM_ENTRIES)
     recordid table_root = ltable.allocTable(xid);
 
     Tcommit(xid);
-    
-    xid = Tbegin();
 
+    writelock(ltable.header_lock,0);
     int lindex = mscheduler.addlogtable(&ltable);
     ltable.setMergeData(mscheduler.getMergeData(lindex));
-    
-    mscheduler.startlogtable(lindex);
 
+    mscheduler.startlogtable(lindex);
+    unlock(ltable.header_lock);
     printf("Stage 1: Writing %d keys\n", NUM_ENTRIES);
     
     struct timeval start_tv, stop_tv, ti_st, ti_end;
@@ -102,7 +101,6 @@ void insertProbeIter(size_t NUM_ENTRIES)
     printf("datasize: %lld\n", (long long)datasize);
     //sleep(20);
 
-    Tcommit(xid);
     xid = Tbegin();
 
 
diff --git a/test/check_mergelarge.cpp b/test/check_mergelarge.cpp
index ca00f3f..02c8237 100644
--- a/test/check_mergelarge.cpp
+++ b/test/check_mergelarge.cpp
@@ -54,13 +54,13 @@ void insertProbeIter(size_t NUM_ENTRIES)
     recordid table_root = ltable.allocTable(xid);
 
     Tcommit(xid);
-    
-    //xid = Tbegin();
 
+    writelock(ltable.header_lock,0);
     int lindex = mscheduler.addlogtable(&ltable);
     ltable.setMergeData(mscheduler.getMergeData(lindex));
-    
+
     mscheduler.startlogtable(lindex);
+    unlock(ltable.header_lock);
 
     printf("Stage 1: Writing %d keys\n", NUM_ENTRIES);
     
diff --git a/test/check_mergetuple.cpp b/test/check_mergetuple.cpp
index 668dbc8..18ba05a 100644
--- a/test/check_mergetuple.cpp
+++ b/test/check_mergetuple.cpp
@@ -112,13 +112,12 @@ void insertProbeIter(size_t NUM_ENTRIES)
     recordid table_root = ltable.allocTable(xid);
 
     Tcommit(xid);
-    
-    xid = Tbegin();
-
+    writelock(ltable.header_lock,0);
     int lindex = mscheduler.addlogtable(&ltable);
     ltable.setMergeData(mscheduler.getMergeData(lindex));
-    
+
     mscheduler.startlogtable(lindex);
+    unlock(ltable.header_lock);
 
     printf("Stage 1: Writing %d keys\n", NUM_ENTRIES);
     
@@ -197,7 +196,6 @@ void insertProbeIter(size_t NUM_ENTRIES)
     printf("\nTREE STRUCTURE\n");
     printf("datasize: %lld\n", datasize);
 
-    Tcommit(xid);
     xid = Tbegin();