Heap allocations in real time critical path lead to significant slow down

[n-eiling]

We should avoid all heap allocations during the simulation as they lead to syscalls and context switches.

For example in a simple simulation involving the Villas interface ~30% of simulation time is spent on this line:

dpsim/dpsim-models/include/dpsim-models/Attribute.h

Line 355 in 9665729

AttributeStatic<T>::make(this->get()));

We could use an arena allocator instead or avoid copying at this position.

[stv0g]

Do we really need to make allocations at all? Doesn't a fixed pre-allocated buffer could work too?

VILLASnode also comes with own allocator (struct Pool)