Exporting Pyro Simulation as VDB problem in Effects Posted June 14 Another way to control memory usage is to control domain size expansion. Sparse can easily get out of control as it enlarges itself to contain the pyro, consuming more memory by dividing the bounding size by the division value. For example missile trails that shoot off in all direction are a bad idea for a single simulation. Perhaps you need to break yours down into smaller manageable simulations that will fit within your physical memory? Or turn up Dissipation to remove old values from the simulation more quickly..?