title: MDX Calculated Member Performance Issue
body: <pre><code>SELECT NON EMPTY {
      [Measures].[Production_Volume]
  } ON COLUMNS,
  NON EMPTY { (
      [Make].[Make ID].[Make ID].ALLMEMBERS
      * [Model].[Model Hierarchy].[MDL].ALLMEMBERS
      * [Customer].[Customer ID].[Customer ID].ALLMEMBERS
  ) } ON ROWS
  FROM [Model_Cube]
  </code></pre>
  <p>This query is taking 10 min</p>
  <p>[Measures].[Production_Volume] is a calculated member in the cube, if I put the definition of this member directly in the query it's taking much lesser time.</p>
  <pre><code>WITH MEMBER [Measures].[Production_Volume] AS 
  ([Measures].[Model Count],
                 ([Status].[Status Type].&amp;[T]
                  ,[Mode].[Mode Type].&amp;[A])
              ) 
      + Sum(
                 ([HYBRID_MODELS]
                  ,[Status].[Status Type].&amp;[C]
                  ,[Mode].[Mode Type].&amp;[A])
              ,[Measures].[Model Count]
              )
  SELECT NON EMPTY {
      [Measures].[Production_Volume]
  } ON COLUMNS,
  NON EMPTY { (
      [Make].[Make ID].[Make ID].ALLMEMBERS
      * [Model].[Model Hierarchy].[MDL].ALLMEMBERS
      * [Customer].[Customer ID].[Customer ID].ALLMEMBERS
  ) } ON ROWS
  FROM [Model_Cube]
  </code></pre>
  <p>this query is taking 4 sec</p>
  <p>Unable to understand the difference between the two, I ran the profiler but couldn't find any difference, except that the first query showed flight recorder snapshot events second query didn't.</p>