Balancing hardware intensity in microprocessor pipelines

The evaluation of architectural tradeoffs is complicated by implications in the circuit domain which are typically not captured in the analysis but substantially affect the results. We propose a metric of hardware intensity (), which is useful for evaluating issues that affect both circuits and architecture. Analyzing data for actual designs, we show how to measure the introduced parameters and discuss variations between observed results and common theoretical assumptions. For a power-efficient design, we derive relations for and supply voltage V under progressively more general situations and illustrate the use of these equations in simple examples. Then we establish a relation between the architectural energy-efficiency metric and hardware intensity, and we derive expressions for evaluating the effect of modifications at the microarchitectural level on processor frequency and power, assuming the optimal tuning of the pipeline. These relations will guide the architect to achieve an energy-optimal balance between architectural complexity and hardware intensity.

[1]  Paul I. Pénzes,et al.  Energy-delay efficiency of VLSI computations , 2002, GLSVLSI '02.

[2]  Victor V. Zyuban,et al.  Optimization of high-performance superscalar architectures for energy efficiency , 2000, ISLPED'00: Proceedings of the 2000 International Symposium on Low Power Electronics and Design (Cat. No.00TH8514).

[3]  Victor V. Zyuban,et al.  Clocking strategies and scannable latches for low power appliacations , 2001, ISLPED '01.

[4]  V. Zyuban,et al.  Clocking strategies and scannable latches for low power applications , 2001, ISLPED'01: Proceedings of the 2001 International Symposium on Low Power Electronics and Design (IEEE Cat. No.01TH8581).

[5]  Anantha P. Chandrakasan,et al.  Low-power CMOS digital design , 1992 .

[6]  B. M. Gordon,et al.  Supply and threshold voltage scaling for low power CMOS , 1997, IEEE J. Solid State Circuits.

[7]  Pradip Bose,et al.  Validation of Turandot, a fast processor model for microarchitecture exploration , 1999, 1999 IEEE International Performance, Computing and Communications Conference (Cat. No.99CH36305).

[8]  V.G. Oklobdzija,et al.  Application of logical effort on design of arithmetic blocks , 2001, Conference Record of Thirty-Fifth Asilomar Conference on Signals, Systems and Computers (Cat.No.01CH37256).

[9]  Michael Gschwind,et al.  Optimizing pipelines for power and performance , 2002, MICRO.

[10]  E. Eugene Schultz,et al.  Hawaii international conference on system sciences , 1992, SGCH.

[11]  Mircea R. Stan Low-power CMOS with subvolt supply voltages , 2001, IEEE Trans. Very Large Scale Integr. Syst..

[12]  Mayan Moudgill,et al.  Environment for PowerPC microarchitecture exploration , 1999, IEEE Micro.

[13]  Thomas D. Burd,et al.  Energy efficient CMOS microprocessor design , 1995, Proceedings of the Twenty-Eighth Annual Hawaii International Conference on System Sciences.

[14]  Victor V. Zyuban,et al.  Unified methodology for resolving power-performance tradeoffs at the microarchitectural and circuit levels , 2002, ISLPED '02.

[15]  Mark Horowitz,et al.  Energy dissipation in general purpose microprocessors , 1996, IEEE J. Solid State Circuits.

[16]  Sameh W. Asaad,et al.  An innovative low-power high-performance programmable signal processor for digital communications , 2003, IBM J. Res. Dev..

[17]  Hendrikus J. M. Veendrick,et al.  Short-circuit dissipation of static CMOS circuitry and its impact on the design of buffer circuits , 1984 .

[18]  Philip N. Strenski,et al.  Gradient-based optimization of custom circuits using a static-timing formulation , 1999, DAC '99.

[19]  Allen M. Peterson,et al.  Energy considerations in multichip-module based multiprocessors , 1991, [1991 Proceedings] IEEE International Conference on Computer Design: VLSI in Computers and Processors.