Sometimes when running a simulation, you will receive an Out of Memory error message. This is typically due to memory allocation for the plot blocks. The plots allocate all their buffer space for the entire run at simulation start. Because each plot trace requires 8*(sim-length/time step) bytes, and even plots that are hidden inside closed compound blocks are allocated and storing data during a run.
The remedy is to remove some plots or decimate the plot data by right-clicking the plot and entering a suitable number in Max Plotted Points under Plot Options.