Implementations of the present disclosure include receiving a sorted list of pages, each page corresponding to a fixed-length contiguous block of virtual memory, and being associated with a respective state, each state indicating a number of off-chip accesses determined for a respective page, and executing an application, which queries an in-memory database provided with a hybrid memory system, and, during execution of the application: identifying at least one page in the sorted list of pages as a page that is to-be-locked during execution of the application based on a threshold, and locking the at least one page in main memory to inhibit swapping of the at least one page by an operating system.