1. A computer-implemented method for populating a plurality of global buffers, the method comprising: receiving from a first processing unit data indicating a number of entries within a first local index buffer generated by the first processing unit, wherein the first processing unit is included in a plurality of processing units; and transmitting to the first processing unit a first base address within a global index buffer that reflects a first location within the global index buffer where the entries within the first local index buffer should be written, wherein the first base address within the first global index buffer is based on a number of entries within the global index buffer already allocated to at least one other processing unit included in the plurality of processing units.