 
 struct TestHeader : DataStoreHeader  {
     
-    var used: Bool = true;
+    var used: Bool = true;  // 1 byte
     
 }
 

    
    
    func testFile() -> NSURL {
        let url = SOTools.tempDirectory()
        return url.URLByAppendingPathComponent("data.db")
    }
    
    func test0Delete() {
        var url = testFile()
        

    
    struct Test : Init {
        
        var a : Int  // 8 bytes
        
        init() {
            a = 0;
