Exploring Hardware Fault Impacts on Different Real Number Representations of the Structural Resilience of TCUs in GPUs

The most recent generations of graphics processing units (GPUs) boost the execution of convolutional operations required by machine learning applications by resorting to specialized and efficient in-chip accelerators (Tensor Core Units or TCUs) that operate on matrix multiplication tiles. Unfortunately, modern cutting-edge semiconductor technologies are increasingly prone to hardware defects, and the trend to highly stress TCUs during the execution of safety-critical and high-performance computing (HPC) applications increases the likelihood of TCUs producing different kinds of failures. In fact, the intrinsic resiliency to hardware faults of arithmetic units plays a crucial role in safety-critical applications using GPUs (e.g., in automotive, space, and autonomous robotics). Recently, new arithmetic formats have been proposed, particularly those suited to neural network execution. However, the reliability characterization of TCUs supporting different arithmetic formats was still lacking. In this work, we quantitatively assessed the impact of hardware faults in TCU structures while employing two distinct formats (floating-point and posit) and using two different configurations (16 and 32 bits) to represent real numbers. For the experimental evaluation, we resorted to an architectural description of a TCU core (PyOpenTCU) and performed 120 fault simulation campaigns, injecting around 200,000 faults per campaign and requiring around 32 days of computation. Our results demonstrate that the posit format of TCUs is less affected by faults than the floating-point one (by up to three orders of magnitude for 16 bits and up to twenty orders for 32 bits). We also identified the most sensible fault locations (i.e., those that produce the largest errors), thus paving the way to adopting smart hardening solutions

Challenges and Opportunities in Near-Threshold DNN Accelerators around Timing Errors

AI evolution is accelerating and Deep Neural Network (DNN) inference accelerators are at the forefront of ad hoc architectures that are evolving to support the immense throughput required for AI computation. However, much more energy efficient design paradigms are inevitable to realize the complete potential of AI evolution and curtail energy consumption. The Near-Threshold Computing (NTC) design paradigm can serve as the best candidate for providing the required energy efficiency. However, NTC operation is plagued with ample performance and reliability concerns arising from the timing errors. In this paper, we dive deep into DNN architecture to uncover some unique challenges and opportunities for operation in the NTC paradigm. By performing rigorous simulations in TPU systolic array, we reveal the severity of timing errors and its impact on inference accuracy at NTC. We analyze various attributes—such as data–delay relationship, delay disparity within arithmetic units, utilization pattern, hardware homogeneity, workload characteristics—and uncover unique localized and global techniques to deal with the timing errors in NTC

Proposal of an Adaptive Fault Tolerance Mechanism to Tolerate Intermittent Faults in RAM

[EN] Due to transistor shrinking, intermittent faults are a major concern in current digital systems. This work presents an adaptive fault tolerance mechanism based on error correction codes (ECC), able to modify its behavior when the error conditions change without increasing the redundancy. As a case example, we have designed a mechanism that can detect intermittent faults and swap from an initial generic ECC to a specific ECC capable of tolerating one intermittent fault. We have inserted the mechanism in the memory system of a 32-bit RISC processor and validated it by using VHDL simulation-based fault injection. We have used two (39, 32) codes: a single error correction-double error detection (SEC-DED) and a code developed by our research group, called EPB3932, capable of correcting single errors and double and triple adjacent errors that include a bit previously tagged as error-prone. The results of injecting transient, intermittent, and combinations of intermittent and transient faults show that the proposed mechanism works properly. As an example, the percentage of failures and latent errors is 0% when injecting a triple adjacent fault after an intermittent stuck-at fault. We have synthesized the adaptive fault tolerance mechanism proposed in two types of FPGAs: non-reconfigurable and partially reconfigurable. In both cases, the overhead introduced is affordable in terms of hardware, time and power consumption.This research was supported in part by the Spanish Government, project TIN2016-81,075-R, and by Primeros Proyectos de Investigacion (PAID-06-18), Vicerrectorado de Investigacion, Innovacion y Transferencia de la Universitat Politecnica de Valencia (UPV), project 20190032.Baraza Calvo, JC.; Gracia-Morán, J.; Saiz-Adalid, L.; Gil Tomás, DA.; Gil, P. (2020). Proposal of an Adaptive Fault Tolerance Mechanism to Tolerate Intermittent Faults in RAM. Electronics. 9(12):1-30. https://doi.org/10.3390/electronics9122074S130912International Technology Roadmap for Semiconductors (ITRS)http://www.itrs2.net/2013-itrs.htmlJeng, S.-L., Lu, J.-C., & Wang, K. (2007). A Review of Reliability Research on Nanotechnology. IEEE Transactions on Reliability, 56(3), 401-410. doi:10.1109/tr.2007.903188Ibe, E., Taniguchi, H., Yahagi, Y., Shimbo, K., & Toba, T. (2010). Impact of Scaling on Neutron-Induced Soft Error in SRAMs From a 250 nm to a 22 nm Design Rule. IEEE Transactions on Electron Devices, 57(7), 1527-1538. doi:10.1109/ted.2010.2047907Boussif, A., Ghazel, M., & Basilio, J. C. (2020). Intermittent fault diagnosability of discrete event systems: an overview of automaton-based approaches. Discrete Event Dynamic Systems, 31(1), 59-102. doi:10.1007/s10626-020-00324-yConstantinescu, C. (2003). Trends and challenges in VLSI circuit reliability. IEEE Micro, 23(4), 14-19. doi:10.1109/mm.2003.1225959Bondavalli, A., Chiaradonna, S., Di Giandomenico, F., & Grandoni, F. (2000). Threshold-based mechanisms to discriminate transient from intermittent faults. IEEE Transactions on Computers, 49(3), 230-245. doi:10.1109/12.841127Contant, O., Lafortune, S., & Teneketzis, D. (2004). Diagnosis of Intermittent Faults. Discrete Event Dynamic Systems, 14(2), 171-202. doi:10.1023/b:disc.0000018570.20941.d2Sorensen, B. A., Kelly, G., Sajecki, A., & Sorensen, P. W. (s. f.). An analyzer for detecting intermittent faults in electronic devices. Proceedings of AUTOTESTCON ’94. doi:10.1109/autest.1994.381590Gracia-Moran, J., Gil-Tomas, D., Saiz-Adalid, L. J., Baraza, J. C., & Gil-Vicente, P. J. (2010). Experimental validation of a fault tolerant microcomputer system against intermittent faults. 2010 IEEE/IFIP International Conference on Dependable Systems & Networks (DSN). doi:10.1109/dsn.2010.5544288Fujiwara, E. (2005). Code Design for Dependable Systems. doi:10.1002/0471792748Hamming, R. W. (1950). Error Detecting and Error Correcting Codes. Bell System Technical Journal, 29(2), 147-160. doi:10.1002/j.1538-7305.1950.tb00463.xSaiz-Adalid, L.-J., Gil-Vicente, P.-J., Ruiz-García, J.-C., Gil-Tomás, D., Baraza, J.-C., & Gracia-Morán, J. (2013). Flexible Unequal Error Control Codes with Selectable Error Detection and Correction Levels. Computer Safety, Reliability, and Security, 178-189. doi:10.1007/978-3-642-40793-2_17Frei, R., McWilliam, R., Derrick, B., Purvis, A., Tiwari, A., & Di Marzo Serugendo, G. (2013). Self-healing and self-repairing technologies. The International Journal of Advanced Manufacturing Technology, 69(5-8), 1033-1061. doi:10.1007/s00170-013-5070-2Maiz, J., Hareland, S., Zhang, K., & Armstrong, P. (s. f.). Characterization of multi-bit soft error events in advanced SRAMs. IEEE International Electron Devices Meeting 2003. doi:10.1109/iedm.2003.1269335Schroeder, B., Pinheiro, E., & Weber, W.-D. (2011). DRAM errors in the wild. Communications of the ACM, 54(2), 100-107. doi:10.1145/1897816.1897844BanaiyanMofrad, A., Ebrahimi, M., Oboril, F., Tahoori, M. B., & Dutt, N. (2015). Protecting caches against multi-bit errors using embedded erasure coding. 2015 20th IEEE European Test Symposium (ETS). doi:10.1109/ets.2015.7138735Kim, J., Sullivan, M., Lym, S., & Erez, M. (2016). All-Inclusive ECC: Thorough End-to-End Protection for Reliable Computer Memory. 2016 ACM/IEEE 43rd Annual International Symposium on Computer Architecture (ISCA). doi:10.1109/isca.2016.60Hwang, A. A., Stefanovici, I. A., & Schroeder, B. (2012). Cosmic rays don’t strike twice. ACM SIGPLAN Notices, 47(4), 111-122. doi:10.1145/2248487.2150989Gil-Tomás, D., Gracia-Morán, J., Baraza-Calvo, J.-C., Saiz-Adalid, L.-J., & Gil-Vicente, P.-J. (2012). Studying the effects of intermittent faults on a microcontroller. Microelectronics Reliability, 52(11), 2837-2846. doi:10.1016/j.microrel.2012.06.004Plasma CPU Modelhttps://opencores.org/projects/plasmaArlat, J., Aguera, M., Amat, L., Crouzet, Y., Fabre, J.-C., Laprie, J.-C., … Powell, D. (1990). Fault injection for dependability validation: a methodology and some applications. IEEE Transactions on Software Engineering, 16(2), 166-182. doi:10.1109/32.44380Gil-Tomas, D., Gracia-Moran, J., Baraza-Calvo, J.-C., Saiz-Adalid, L.-J., & Gil-Vicente, P.-J. (2012). Analyzing the Impact of Intermittent Faults on Microprocessors Applying Fault Injection. IEEE Design & Test of Computers, 29(6), 66-73. doi:10.1109/mdt.2011.2179514Rashid, L., Pattabiraman, K., & Gopalakrishnan, S. (2010). Modeling the Propagation of Intermittent Hardware Faults in Programs. 2010 IEEE 16th Pacific Rim International Symposium on Dependable Computing. doi:10.1109/prdc.2010.52Amiri, M., Siddiqui, F. M., Kelly, C., Woods, R., Rafferty, K., & Bardak, B. (2016). FPGA-Based Soft-Core Processors for Image Processing Applications. Journal of Signal Processing Systems, 87(1), 139-156. doi:10.1007/s11265-016-1185-7Hailesellasie, M., Hasan, S. R., & Mohamed, O. A. (2019). MulMapper: Towards an Automated FPGA-Based CNN Processor Generator Based on a Dynamic Design Space Exploration. 2019 IEEE International Symposium on Circuits and Systems (ISCAS). doi:10.1109/iscas.2019.8702589Mittal, S. (2018). A survey of FPGA-based accelerators for convolutional neural networks. Neural Computing and Applications, 32(4), 1109-1139. doi:10.1007/s00521-018-3761-1Intel Completes Acquisition of Alterahttps://newsroom.intel.com/news-releases/intel-completes-acquisition-of-altera/#gs.mi6ujuAMD to Acquire Xilinx, Creating the Industry’s High Performance Computing Leaderhttps://www.amd.com/en/press-releases/2020-10-27-amd-to-acquire-xilinx-creating-the-industry-s-high-performance-computingKim, K. H., & Lawrence, T. F. (s. f.). Adaptive fault tolerance: issues and approaches. [1990] Proceedings. Second IEEE Workshop on Future Trends of Distributed Computing Systems. doi:10.1109/ftdcs.1990.138292Gonzalez, O., Shrikumar, H., Stankovic, J. A., & Ramamritham, K. (s. f.). Adaptive fault tolerance and graceful degradation under dynamic hard real-time scheduling. Proceedings Real-Time Systems Symposium. doi:10.1109/real.1997.641271Jacobs, A., George, A. D., & Cieslewski, G. (2009). Reconfigurable fault tolerance: A framework for environmentally adaptive fault mitigation in space. 2009 International Conference on Field Programmable Logic and Applications. doi:10.1109/fpl.2009.5272313Shin, D., Park, J., Park, J., Paul, S., & Bhunia, S. (2017). Adaptive ECC for Tailored Protection of Nanoscale Memory. IEEE Design & Test, 34(6), 84-93. doi:10.1109/mdat.2016.2615844Silva, F., Muniz, A., Silveira, J., & Marcon, C. (2020). CLC-A: An Adaptive Implementation of the Column Line Code (CLC) ECC. 2020 33rd Symposium on Integrated Circuits and Systems Design (SBCCI). doi:10.1109/sbcci50935.2020.9189901Mukherjee, S. S., Emer, J., Fossum, T., & Reinhardt, S. K. (s. f.). Cache scrubbing in microprocessors: myth or necessity? 10th IEEE Pacific Rim International Symposium on Dependable Computing, 2004. Proceedings. doi:10.1109/prdc.2004.1276550Saleh, A. M., Serrano, J. J., & Patel, J. H. (1990). Reliability of scrubbing recovery-techniques for memory systems. IEEE Transactions on Reliability, 39(1), 114-122. doi:10.1109/24.52622X9SRA User’s Manual (Rev. 1.1)https://www.manualshelf.com/manual/supermicro/x9sra/user-s-manual-1-1.htmlChishti, Z., Alameldeen, A. R., Wilkerson, C., Wu, W., & Lu, S.-L. (2009). Improving cache lifetime reliability at ultra-low voltages. Proceedings of the 42nd Annual IEEE/ACM International Symposium on Microarchitecture - Micro-42. doi:10.1145/1669112.1669126Datta, R., & Touba, N. A. (2011). Designing a fast and adaptive error correction scheme for increasing the lifetime of phase change memories. 29th VLSI Test Symposium. doi:10.1109/vts.2011.5783773Kim, J., Lim, J., Cho, W., Shin, K.-S., Kim, H., & Lee, H.-J. (2016). Adaptive Memory Controller for High-performance Multi-channel Memory. JSTS:Journal of Semiconductor Technology and Science, 16(6), 808-816. doi:10.5573/jsts.2016.16.6.808Yuan, L., Liu, H., Jia, P., & Yang, Y. (2015). Reliability-Based ECC System for Adaptive Protection of NAND Flash Memories. 2015 Fifth International Conference on Communication Systems and Network Technologies. doi:10.1109/csnt.2015.23Zhou, Y., Wu, F., Lu, Z., He, X., Huang, P., & Xie, C. (2019). SCORE. ACM Transactions on Architecture and Code Optimization, 15(4), 1-25. doi:10.1145/3291052Lu, S.-K., Li, H.-P., & Miyase, K. (2018). Adaptive ECC Techniques for Reliability and Yield Enhancement of Phase Change Memory. 2018 IEEE 24th International Symposium on On-Line Testing And Robust System Design (IOLTS). doi:10.1109/iolts.2018.8474118Chen, J., Andjelkovic, M., Simevski, A., Li, Y., Skoncej, P., & Krstic, M. (2019). Design of SRAM-Based Low-Cost SEU Monitor for Self-Adaptive Multiprocessing Systems. 2019 22nd Euromicro Conference on Digital System Design (DSD). doi:10.1109/dsd.2019.00080Wang, X., Jiang, L., & Chakrabarty, K. (2020). LSTM-based Analysis of Temporally- and Spatially-Correlated Signatures for Intermittent Fault Detection. 2020 IEEE 38th VLSI Test Symposium (VTS). doi:10.1109/vts48691.2020.9107600Ebrahimi, H., & G. Kerkhoff, H. (2018). Intermittent Resistance Fault Detection at Board Level. 2018 IEEE 21st International Symposium on Design and Diagnostics of Electronic Circuits & Systems (DDECS). doi:10.1109/ddecs.2018.00031Ebrahimi, H., & Kerkhoff, H. G. (2020). A New Monitor Insertion Algorithm for Intermittent Fault Detection. 2020 IEEE European Test Symposium (ETS). doi:10.1109/ets48528.2020.9131563Hsiao, M. Y. (1970). A Class of Optimal Minimum Odd-weight-column SEC-DED Codes. IBM Journal of Research and Development, 14(4), 395-401. doi:10.1147/rd.144.0395Benso, A., & Prinetto, P. (Eds.). (2004). Fault Injection Techniques and Tools for Embedded Systems Reliability Evaluation. Frontiers in Electronic Testing. doi:10.1007/b105828Gracia, J., Saiz, L. J., Baraza, J. C., Gil, D., & Gil, P. J. (2008). Analysis of the influence of intermittent faults in a microcontroller. 2008 11th IEEE Workshop on Design and Diagnostics of Electronic Circuits and Systems. doi:10.1109/ddecs.2008.4538761ZC702 Evaluation Board for the Zynq-7000 XC7Z020 SoChttps://www.xilinx.com/support/documentation/boards_and_kits/zc702_zvik/ug850-zc702-eval-bd.pd

Circuits and Systems Advances in Near Threshold Computing

Modern society is witnessing a sea change in ubiquitous computing, in which people have embraced computing systems as an indispensable part of day-to-day existence. Computation, storage, and communication abilities of smartphones, for example, have undergone monumental changes over the past decade. However, global emphasis on creating and sustaining green environments is leading to a rapid and ongoing proliferation of edge computing systems and applications. As a broad spectrum of healthcare, home, and transport applications shift to the edge of the network, near-threshold computing (NTC) is emerging as one of the promising low-power computing platforms. An NTC device sets its supply voltage close to its threshold voltage, dramatically reducing the energy consumption. Despite showing substantial promise in terms of energy efficiency, NTC is yet to see widescale commercial adoption. This is because circuits and systems operating with NTC suffer from several problems, including increased sensitivity to process variation, reliability problems, performance degradation, and security vulnerabilities, to name a few. To realize its potential, we need designs, techniques, and solutions to overcome these challenges associated with NTC circuits and systems. The readers of this book will be able to familiarize themselves with recent advances in electronics systems, focusing on near-threshold computing

High-Density Solid-State Memory Devices and Technologies

This Special Issue aims to examine high-density solid-state memory devices and technologies from various standpoints in an attempt to foster their continuous success in the future. Considering that broadening of the range of applications will likely offer different types of solid-state memories their chance in the spotlight, the Special Issue is not focused on a specific storage solution but rather embraces all the most relevant solid-state memory devices and technologies currently on stage. Even the subjects dealt with in this Special Issue are widespread, ranging from process and design issues/innovations to the experimental and theoretical analysis of the operation and from the performance and reliability of memory devices and arrays to the exploitation of solid-state memories to pursue new computing paradigms

Multi-Unit Serial Polynomial Multiplier to Accelerate NTRU-Based Cryptographic Schemes in IoT Embedded Systems

Concern for the security of embedded systems that implement IoT devices has become a crucial issue, as these devices today support an increasing number of applications and services that store and exchange information whose integrity, privacy, and authenticity must be adequately guaranteed. Modern lattice-based cryptographic schemes have proven to be a good alternative, both to face the security threats that arise as a consequence of the development of quantum computing and to allow efficient implementations of cryptographic primitives in resource-limited embedded systems, such as those used in consumer and industrial applications of the IoT. This article describes the hardware implementation of parameterized multi-unit serial polynomial multipliers to speed up time-consuming operations in NTRU-based cryptographic schemes. The flexibility in selecting the design parameters and the interconnection protocol with a general-purpose processor allow them to be applied both to the standardized variants of NTRU and to the new proposals that are being considered in the post-quantum contest currently held by the National Institute of Standards and Technology, as well as to obtain an adequate cost/performance/security-level trade-off for a target application. The designs are provided as AXI4 bus-compliant intellectual property modules that can be easily incorporated into embedded systems developed with the Vivado design tools. The work provides an extensive set of implementation and characterization results in devices of the Xilinx Zynq-7000 and Zynq UltraScale+ families for the different sets of parameters defined in the NTRUEncrypt standard. It also includes details of their plug and play inclusion as hardware accelerators in the C implementation of this public-key encryption scheme codified in the LibNTRU library, showing that acceleration factors of up to 3.1 are achieved when compared to pure software implementations running on the processing systems included in the programmable devices.European Union 952622Ministerio de Ciencia e Innovación PID2020-116664RB100, 10.13039/50110001103

Reliability and Security Assessment of Modern Embedded Devices

L'abstract è presente nell'allegato / the abstract is in the attachmen

Dependable Embedded Systems

This Open Access book introduces readers to many new techniques for enhancing and optimizing reliability in embedded systems, which have emerged particularly within the last five years. This book introduces the most prominent reliability concerns from today’s points of view and roughly recapitulates the progress in the community so far. Unlike other books that focus on a single abstraction level such circuit level or system level alone, the focus of this book is to deal with the different reliability challenges across different levels starting from the physical level all the way to the system level (cross-layer approaches). The book aims at demonstrating how new hardware/software co-design solution can be proposed to ef-fectively mitigate reliability degradation such as transistor aging, processor variation, temperature effects, soft errors, etc. Provides readers with latest insights into novel, cross-layer methods and models with respect to dependability of embedded systems; Describes cross-layer approaches that can leverage reliability through techniques that are pro-actively designed with respect to techniques at other layers; Explains run-time adaptation and concepts/means of self-organization, in order to achieve error resiliency in complex, future many core systems

Technology 2001: The Second National Technology Transfer Conference and Exposition, volume 1

Papers from the technical sessions of the Technology 2001 Conference and Exposition are presented. The technical sessions featured discussions of advanced manufacturing, artificial intelligence, biotechnology, computer graphics and simulation, communications, data and information management, electronics, electro-optics, environmental technology, life sciences, materials science, medical advances, robotics, software engineering, and test and measurement

Proceedings of the Flat-plate Solar Array Project Research Forum on the High-speed Growth and Characterization of Crystals for Solar Cells

Theoretical and experimental phenomena, applications, and characterization including stress/strain and other problem areas that limit the rate of growth of crystals suitable for processing into efficient, cost-effective solar cells are discussed. Melt spinning, ribbon growth, rapid solidification, laser recrystallization, and ignot growth of silicon and metals are also discussed