A system, method, and computer-readable medium for grouping of database object access counts per processing module in a parallel processing system. Each processing module manages an intermediate cache allocated thereto that stores database object access counts local to the respective processing module. The processing modules are configured in a hierarchical configuration. The intermediate caches managed by the processing modules at the lowest level of the configuration are forwarded to a parent processing module and merged with the intermediate cache allocated to the parent processing module. A root processing module merges the intermediate caches received from one or more parent processing modules with the root processing module's intermediate cache to generate a final cache. An objects access count data structure is then generated by the root processing module.