Exploring power management in multi-core systems

Abstract — Power dissipation has become a critical design met-ric in microprocessor-based system design. In a multi-core sys-tem, running multiple applications, power and performance can be dynamically traded off using an integrated power management (PM) unit. This PM unit monitors the performance and power of each core and dynamically adjusts the individual voltages and fre-quencies in order to maximize system performance under a given power budget (usually set by the operating system). This paper presents a performance and power analysis methodology, featur-ing a simulation model for multi-core systems that can be easily reconfigured for different scenarios and a PM infrastructure for the exploration and analysis of PM algorithms. Two algorithms have been implemented: one for discrete and one for continuous power modes based on non-linear programming. Extensive exper-iments are reported, illustrating the effect of power management both at the core and the chip level. I

Performance modeling for early analysis of multi-core systems

Performance analysis of microprocessors is a critical step in defining the microarchitecture, prior to register-transfer-level (RTL) design. In complex chip multiprocessor systems, including multiple cores, caches and busses, this problem is compounded by complex performance interactions between cores, caches and interconnections, as well as by tight interdependencies between performance, power and physical characteristics of the design (i.e., floorplan). Although there are many point tools for the analysis of performance, or power, or floorplan of complex systems-on-chip (SoCs), there are surprisingly few works on an integrated tool that is capable of analyzing these various system characteristics simultaneously and allow the user to explore different design configurations and their effect on performance, power, size and thermal aspects. This paper describes an integrated tool for early analysis of performance, power, physical and thermal characteristics of multi-core systems. It includes cycle-accurate, transaction-level SystemC-based performance models of POWER processors and system components (i.e., caches, buses). Power models, for power computation, physical models for floorplanning and packaging models for thermal analysis are also included. The tool allows the user to build different systems by selecting components from a library and connecting them together in a visual environment. Using these models, users can simulate and dynamically analyze the performance, power and thermal aspects of multi-core systems