If you are using a computer with multiple processors—for example, dual cores—you can use a new "multi-threaded" option in Microsoft Excel 2007 or later to split up spreadsheet model recalculations into separate tasks. These tasks can then be run independently on each processor to speed up the overall recalculation time. Since time for one calculation is reduced, the time to run an entire simulation is also reduced. For two processors, the increase in simulation speed can be roughly anywhere from 10% to 50%, depending on the model. Crystal Ball uses Microsoft Excel's multi-threading setting by default when performing simulation calculations in Microsoft Excel 2007 on multi-core or multi-processor computers.
To activate multi-threading in Microsoft Excel 2007 or later:To use multi-threading efficiently, you should be working with a spreadsheet model that:
Is large (that is, it takes more than 0.5 sec for each recalculation).
Can easily be divided into separate tasks by Microsoft Excel 2007 or later (for example, it might have separate chains or groups of formulas that do not depend on each other).
Is running at Normal Speed, since Extreme Speed does not increase benefits with this feature.
Depending on model size, it is possible that performance can be improved on multi-core or multi-processor computers by manually disabling the use of multi-threading. In general, smaller models run more slowly with multi-threading and larger models run faster. Changing this setting on single-core or single-processor computers has no impact. To disable multi-threading in Microsoft Excel 2007 before running Crystal Ball models, consult the Microsoft Excel documentation.