5 Replies Latest reply: Aug 10, 2012 1:02 AM by Rob Wunderlich RSS

    Why is SUM in load script so slow?

      I have a load script where I am loading a table with ~1M rows.

      The next thing I do is reload it (resident load) as a different table and do a SUM on one of the fields (group by two other fields).

       

      Table2:

      LOAD

         Field1,

         Field2,

         Sum(Metric) AS SumOfMetric

      Resident Table1

      Group By

         Field1,

         Field2;

       

      It takes a very long time to run (>20 minutes), which is surprising since the original 1Mrow table loaded in a few seconds.

      I have a server with 16 cores, but only one core is being used at any given time during the SUM.

       

      Any idea why this is so slow or how I can speed it up?

      The same operation in a chart in the UI is super fast!