Wind tunnel parameter slows down smoke simulation.

The stop condition skips the current iteration.

When using skin with Groups of some primitives, this work slowly: the cooking time increases exponentially with an increase in the number of primitives (100.000 and more). Use foreach for some primitives (e. g., 1000):

i@skinGroup = i@primnum / 1000;

The expression to activate the solving only in the integer value of the frame:

$FF%1 == 0

For example, if you use sub-steps for source particles once in a frame.

The two way switch turns off the entire branch, and it is not executed. “If” block does too. But all operators must be inside it for this.
When using the switch, all inputs are executed.

It is necessary to check Solve on creation frame for the packed animated static object if we use it in constraints. Or you need to set the same position of the object in the first and second frames of the simulation. This is due to the initialization of bullet attributes.

The bounce of a structure assembled using a cone twist is strongly influenced by the bias parameter in cone twist relationship. If it is smaller, then the object rebounds less on impact.

The light attenuation ramp must be used in tandem with the active radius. This gives a render time reduction of about 15 percent.

Keep in mind that normals are important for rendering when using a uniform volume. If the object does not feel the volume, and it is very dense, then you need to do a reverse.

You need to set a border = const with value = 0 for a heat field. A heat border is imported from the dynamics with a value of -0.01. This can affect shading.