Ramulator 2.1: A Composable Memory System Simulator for Modern DRAM Systems

Ramulator 2.1 addresses the problem of simulating modern and emerging DRAM systems with limited support for advanced features and poor usability. The method introduces a Python-based modeling interface with two-way code generation, hiding low-level C++ behind high-level DRAM specifications. Experimental evidence shows the simulator enables rapid creation of DRAM variants and automated design-space exploration, validated through fine-grained timing constraints and system-level performance curves. This matters because it provides an open-source, extensible, and trustworthy simulation framework for advancing memory system research.