V-Ray GI node automates calculation of global illumination in V-Ray. This node has two modes: reading and writing. The path to GI files is generated automatically.
Working process with a node: first of all, create the main pass and the pass for GI precalculation. The precalculation pass must be above the main to be rendered first. Then add the V-ray GI node to the precalculation pass and select the required recording mode. Add V-ray GI node to the main pass as wel and select reading mode. Select the precalculation pass as a source of GI. V-ray GI of a main pass will automatically understand where to look for the GI files and which mode the GI uses.