System and method for efficient multi-GPU rendering of geometry by subdividing geometry

A computer system comprising:

• a processor;
• memory coupled to the processor and having stored therein instructions that, if executed by the computer system, cause the computer system to execute a method for graphics processing, comprising:
• rendering graphics for an application using a plurality of graphics processing units (GPUs);
• using the plurality of GPUs in collaboration for rendering an image frame including a plurality of pieces of geometry;
• during the rendering of the image frame, subdividing one or more of the plurality of pieces of geometry into a plurality of smaller portions of geometry, and dividing responsibility for rendering these smaller portions of geometry among the plurality of GPUs, wherein each of the smaller portions of geometry is processed by a corresponding GPU;
• determining timing information during a first phase of rendering for the plurality of GPUs, wherein the timing information is related to execution of the first phase of renderin for the image frame;
• and
• reassigning a smaller portion of geometry from a first GPU to a second GPU for processing during the first phase of rendering based on the timing information,
• wherein the first phase of rendering includes one of a geometry analysis phase of rendering, or a Z pre-pass phase of rendering, or a geometry pass phase of rendering.

A method for graphics processing, comprising:

• rendering graphics for an application using a plurality of graphics processing units (GPU);
• using the plurality of GPUs in collaboration for rendering an image frame including a plurality of pieces of geometry;
• during the rendering of the image frame, subdividing one or more of the plurality of pieces of geometry into a plurality of smaller portions of geometry, and dividing responsibility for rendering the plurality of smaller portions of geometry among the plurality of GPUs, wherein each of the plurality of smaller portions of geometry is processed by a first corresponding GPU;
• for one or more pieces of geometry that are not subdivided, dividing responsiblity for rendering the one or more pieces of geometry that are not subdivided among the plurality of GPUs, wherein each of the one or more pieces of geometry that are not subdivided is processed by a second corresponding GPU;
• using the plurality of GPUs in collaboration to generate a Z-buffer for the image frame including the plurality of pieces of geometry during a Z pre-pass phase of rendering;
• generating information during the Z pre-pass phase of rendering regarding the plurality of pieces of geometry of the image frame and their relations to a plurality of screen regions;
• assigning the plurality of screen regions to the plurality of GPUs based on the information for the rendering of the image frame during a geometry pass phase of rendering;
• rendering, during the geometry pass phase of rendering, the plurality of pieces of geometry at each of the plurality of GPUs based on GPU to screen region assignments determined from the assigning the plurality of screen regions to the plurality of GPUs;
• and
• reassigning a first piece of geometry initially assigned to a first GPU for rendering during the geometry pass phase to a second GPU.