Command Buffers can encode multiple render or blit passes, provided that the previous render pass has completed before a new one is added. Since there is some overhead in creating and submitting a cmd buffer, we can slightly improve CPU performance on filter heavy scenes (backdrop blur benchmark) by utilizing the same cmd buffer in parts of the filter graph.

For example, the gaussian blur shader performs multiple render passes in sequential order, but uses a different cmd buffer for each one. These could be combined into a single cmd buffer.