Inflorescences are flower-bearing shoots that originate from pools of stem cells in shoot apical meristems (SAM).Inflorescence architecture is determined by a process of meristem maturation,during which stem cell fate...Inflorescences are flower-bearing shoots that originate from pools of stem cells in shoot apical meristems (SAM).Inflorescence architecture is determined by a process of meristem maturation,during which stem cell fate switches from a vegetative to a reproductive growth program.A major factor in plant reproductive success in nature and yield in agriculture is the number of branches and flowers on inflorescences (Kobayashi and Weigel,2007;展开更多
With continuous technology scaling, on-chip structures are becoming more and more susceptible to soft errors. Architectural vulnerability factor (AVF) has been introduced to quantify the architectural vulnerability ...With continuous technology scaling, on-chip structures are becoming more and more susceptible to soft errors. Architectural vulnerability factor (AVF) has been introduced to quantify the architectural vulnerability of on-chip structures to soft errors. Recent studies have found that designing soft error protection techniques with the awareness of AVF is greatly helpful to achieve a tradeoff between performance and reliability for several structures (i.e., issue queue, reorder buffer). Cache is one of the most susceptible components to soft errors and is commonly protected with error correcting codes (ECC). However, protecting caches closer to the processor (i.e., L1 data cache (LID)) using ECC could result in high overhead. Protecting caches without accurate knowledge of the vulnerability characteristics may lead to over-protection. Therefore, designing AVF-aware ECC is attractive for designers to balance among performance, power and reliability for cache, especially at early design stage. In this paper, we improve the methodology of cache AVF computation and develop a new AVF estimation framework, soft error reliability analysis based on SimpleScalar. Then we characterize dynamic vulnerability behavior of LID and detect the correlations between L1D AVF and various performance metrics. We propose to employ Bayesian additive regression trees to accurately model the variation of L1D AVF and to quantitatively explain the important effects of several key performance metrics on L1D AVF. Then, we employ bump hunting technique to reduce the complexity of L1D AVF prediction and extract some simple selecting rules based on several key performance metrics, thus enabling a simplified and fast estimation of L1D AVF. Based on the simplified and fast estimation of L1D AVF, intervals of high L1D AVF can be identified online, enabling us to develop the AVF-aware ECC technique to reduce the overhead of ECC. Experimental results show that compared with traditional ECC technique which provides complete ECC protection throughout the entire lifetime of a program, AVF-aware ECC technique reduces the L1D access latency by 35% and saves power consumption by 14% for SPEC2K benchmarks averagely.展开更多
基金supported by startup funding to C.X.from State Key Laboratory of Plant Genomics and Institute of Genetics and Developmental Biology,Chinese Academy of Sciences,and a National Science Foundation grant(IOS-1556171)to Z.B.L
文摘Inflorescences are flower-bearing shoots that originate from pools of stem cells in shoot apical meristems (SAM).Inflorescence architecture is determined by a process of meristem maturation,during which stem cell fate switches from a vegetative to a reproductive growth program.A major factor in plant reproductive success in nature and yield in agriculture is the number of branches and flowers on inflorescences (Kobayashi and Weigel,2007;
基金Supported by the National Natural Science Foundation of China under Grant Nos. 60970036 and 60873016the National High Technology Development 863 Program of China under Grant Nos. 2009AA01Z102 and 2009AA01Z124
文摘With continuous technology scaling, on-chip structures are becoming more and more susceptible to soft errors. Architectural vulnerability factor (AVF) has been introduced to quantify the architectural vulnerability of on-chip structures to soft errors. Recent studies have found that designing soft error protection techniques with the awareness of AVF is greatly helpful to achieve a tradeoff between performance and reliability for several structures (i.e., issue queue, reorder buffer). Cache is one of the most susceptible components to soft errors and is commonly protected with error correcting codes (ECC). However, protecting caches closer to the processor (i.e., L1 data cache (LID)) using ECC could result in high overhead. Protecting caches without accurate knowledge of the vulnerability characteristics may lead to over-protection. Therefore, designing AVF-aware ECC is attractive for designers to balance among performance, power and reliability for cache, especially at early design stage. In this paper, we improve the methodology of cache AVF computation and develop a new AVF estimation framework, soft error reliability analysis based on SimpleScalar. Then we characterize dynamic vulnerability behavior of LID and detect the correlations between L1D AVF and various performance metrics. We propose to employ Bayesian additive regression trees to accurately model the variation of L1D AVF and to quantitatively explain the important effects of several key performance metrics on L1D AVF. Then, we employ bump hunting technique to reduce the complexity of L1D AVF prediction and extract some simple selecting rules based on several key performance metrics, thus enabling a simplified and fast estimation of L1D AVF. Based on the simplified and fast estimation of L1D AVF, intervals of high L1D AVF can be identified online, enabling us to develop the AVF-aware ECC technique to reduce the overhead of ECC. Experimental results show that compared with traditional ECC technique which provides complete ECC protection throughout the entire lifetime of a program, AVF-aware ECC technique reduces the L1D access latency by 35% and saves power consumption by 14% for SPEC2K benchmarks averagely.