  The advent of CPU-attached persistent memory technology, such as Intel's
Optane Persistent Memory Modules (PMM), has brought with it new opportunities
for storage. In 2018, IBM Research Almaden began investigating and developing a
new enterprise-grade storage solution directly aimed at this emerging
technology. MCAS (Memory Centric Active Storage) defines an evolved
network-attached key-value store that offers both near-data compute and the
ability to layer enterprise-grade data management services on shared persistent
memory. As a converged memory-storage tier, MCAS moves towards eliminating the
traditional separation of compute and storage, and thereby unifying the data
space. This paper provides an in-depth review of the MCAS architecture and
implementation, as well as general performance results.
