Jeff Pool
ABSTRACT
In this work, we seek to realize energy savings in modern pixel shaders by reducing the precision of their arithmetic. We explore three schemes for controlling this reduction. The first is a static analysis technique, which analyzes shader programs to choose precision with guaranteed error bounds. This approach may be too conservative in practice since it cannot take advantage of run-time information, so we also examine two methods that take the actual data values into account - a programmer-directed approach and a closed-loop error-tracking approach, both of which can lead to higher savings. To use this last method, we developed several heuristics to control how the precisions will change over time. We simulate several series of frames from commercial applications to evaluate the performance of these different schemes. The average savings found by the static and dynamic approaches are 31%, 70%, and 62% in the pixel shader's arithmetic, respectively, which could result in as much as a 10--20% savings of the GPU's energy as a whole.
- Akeley, K., and Su, J. 2006. Minimum triangle separation for correct z-buffer occlusion. In 21st ACM SIGGRAPH/EUROGRAPHICS Symposium on Graphics Hardware, ACM, New York, NY, USA, GH '06, 27--30. Google Scholar
Digital Library
- AMD, 2008. Rendermonkey 1.82. http://developer.amd.com/archive/gpu/rendermonkey/pages/default.aspx, Dec.Google Scholar
- ATTILA, 2011. Traces - AttilaWiki. http://attila.ac.upc.edu/traceList/, Accessed: April 2011.Google Scholar
- Baker, P., 2011. Metaballs II. http://www.paulsprojects.net/metaballs2/metaballs2.html, Apr.Google Scholar
- Callaway, T., and Swartzlander, E. E., J. 1997. Power-delay characteristics of CMOS multipliers. In 13th IEEE Symposium on Computer Arithmetic, 1997, 26--32. Google ScholarDigital Library
- Chittamuru, J., Burleson, W., and Euh, J. 2003. Dynamic wordlength variation for low-power 3D graphics texture mapping. In 2003 IEEE Workshop on Signal Processing Systems, SIPS '03, 251--256.Google Scholar
- del Barrio, V., Gonzalez, C., Roca, J., Fernandez, A., and Espasa, R. 2006. ATTILA: a cycle-level execution-driven simulator for modern GPU architectures. In 2006 IEEE International Symposium on Performance Analysis of Systems and Software, ISPASS '06, 231--241.Google Scholar
- EA Black Box, 2008. Need for Speed: Undercover. http://undercover.needforspeed.com/home.action, Nov.Google Scholar
- Hao, X., and Varshney, A. 2001. Variable-precision rendering. In 2001 Symposium on Interactive 3D Graphics, ACM, New York, NY, USA, I3D '01, 149--158. Google ScholarDigital Library
- Huang, Z., and Ercegovac, M. 2002. Two-dimensional signal gating for low-power array multiplier design. In IEEE International Symposium on Circuits and Systems, ISCAS '02, 489--492.Google Scholar
- id, 2005. Doom 3. http://idsoftware.com/games/doom/doom3/index.php, Apr.Google Scholar
- Lee, Y., Park, J., and Chung, K. 2007. Design of low power MAC operator with dual precision mode. In 13th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications, RTCSA '07, 309--318. Google ScholarDigital Library
- Lee, Y., Jung, H., and Chung, K. 2009. Low power MAC design with variable precision support. IEICE Transactions on Fundamentals of Electronics, Communications and Computer Science 92-A, 7, 1623--1632.Google Scholar
- Liu, Y., and Furber, S. 2004. The design of a low power asynchronous multiplier. In 2004 International Symposium on Low Power Electronics and Design, ISLPED '04, 301--306. Google ScholarDigital Library
- Microsoft, 2011. PIX. http://msdn.microsoft.com/en-us/library/ee417062(v=VS.85).aspx, Apr.Google Scholar
- NVIDIA Corporation, 2010. NVIDIA Direct3D SDK 10 Code Samples. http://developer.download.nvidia.com/SDK/10.5/direct3d/samples.html, Jun.Google Scholar
- Pool, J., Lastra, A., and Singh, M. 2008. Energy-precision tradeoffs in mobile graphics processing units. In 2008 IEEE International Conference on Computer Design, ICCD '08, 60--67.Google Scholar
- Pool, J., Lastra, A., and Singh, M. 2010. An energy model for graphics processing units. In 2010 IEEE International Conference on Computer Design, ICCD '10, 409--416.Google Scholar
- Pool, J., Lastra, A., and Singh, M. 2011. Power-gated arithmetic circuits for energy-precision tradeoffs in mobile graphics processing units. Journal of Low Power Electronics 7, 2 (April), 148--162.Google ScholarCross Ref
- Tong, J., Nagle, D., and Rutenbar, R. 2000. Reducing power by optimizing the necessary precision/range of floating-point arithmetic. IEEE Transactions on Very Large Scale Integration (VLSI) Systems 8, 3 (jun), 273--286. Google ScholarDigital Library
- Valve, 2005. Half-Life 2: Lost Coast. http://store.steampowered.com/app/340, Oct.Google Scholar
- Wilkinson, J. H. 1959. Rounding errors in algebraic processes. In 1959 International Conference on Information Processing, 44--53.Google Scholar
Index Terms
- Precision selection for energy-efficient pixel shaders
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