Chapter 15

One of the most frequently asked questions when performing almost any scientific computation is: how do I make my simulation faster? Or, equivalently, why is my simulation running so slowly?

The spectral element method is no exception to this rule. The purpose of this section is to highlight some of the easiest parameters that can be tuned to attain optimum performance for a given simulation.

Details are kept as untechnical as possible, but some background information on the underlying numerical methods is necessary in order to understand the various options available and the implications that they can have on your simulation.

In the current version of the library we now attempt to turn on some of these optimisations automatically and so you will likely observe a session.opt file appear in your directory which can be viewed to see what settings are being selected.

 15.1 Collections and MatrixFree operations
  15.1.1 Automatic tuning and the –writeoptfile command line option
  15.1.2 Manually selecting the COLLECTIONS section
  15.1.3 Collection size