Scalable architecture enabling large memory system for in-memory computations

A memory system provides deduplication of user data in the physical memory space of the system for user data that is duplicated in the virtual memory space of a host system. A transaction manager (TM) uses a transaction table to maintain data coherency and data concurrency for the virtual memory space. A write data engine manager (WDEM) uses an outstanding bucket number and command queues to maintain data coherency and data concurrency for the physical memory space. The WDEM receives data write requests from the TM and sends a corresponding write command to a selected command queue. A write data engine responds to a write command in a command queue by storing the data in an overflow memory region if the data is not duplicated in the virtual memory space, or by incrementing a reference counter for the data if the data is duplicated in the virtual memory space.