CPU load during optimization

Xoptfoil2 makes intensive use of multi threading during particle swarm optimization. Here each particle gets its own (next free) thread to perform the CPU-intensive aerodynamic viscous with xfoil.

A special parameter in the input file allows to control how many CPU threads Xoptfoil2 should use during optimization:

&optimization_options                            
  cpu_threads      = nThreads                         
/  

If nThreads is positive, then this number of threads will be used. If nThreads is negative, then the maximum avaiable number of threads will bei reduced by nThreads.

In this example an optimization was just started using all available threads.

The default setting is cpu_threads = -1 leaving one thread free to allow more or less normal working with the PC.