With the rapid improvement of computation capability in high performance supercomputer system, the imbalance of performance between computation subsystem and storage subsystem has become more and more serious, especia...With the rapid improvement of computation capability in high performance supercomputer system, the imbalance of performance between computation subsystem and storage subsystem has become more and more serious, especially when various big data are produced ranging from tens of gigabytes up to terabytes. To reduce this gap, large-scale storage systems need to be designed and implemented with high performance and scalability. MilkyWay-2 （TH-2） supercomputer system with peak performance 54.9 Props, definitely has this kind of requirement for storage system. This paper mainly introduces the storage system in MilkyWay-2 supercomputer, including the hardware architecture and the parallel file system. The storage system in MilkyWay-2 supercomputer exploits a novel hybrid hierarchy storage architecture to enable high scalability of I/O clients, I/O bandwidth and storage capacity. To fit this architecture, a user level virtualized file system, named H^2FS, is designed and implemented which can cooperate local storage and shared storage together into a dynamic single namespace to optimize I/O performance in IO-intensive applications. The evaluation results show that the storage system in MilkyWay-2 supercomputer can satisfy the critical requirements in large scale supercomputer, such as performance and scalability.展开更多
The cost of the central register file and the size of the program code limit the scalability of very long instruction word（VLIW） processors with increasing numbers of functional units.This paper presents the archite...The cost of the central register file and the size of the program code limit the scalability of very long instruction word（VLIW） processors with increasing numbers of functional units.This paper presents the architectural design of a six-way VLIW digital signal processor（DSP） with clustered register files.The architecture uses a variable length instruction set and supports dynamic instruction dispatching.The one-level memory system architecture of the processor includes 16-KB instruction and data caches and 16-KB instruction and data on-chip RAM.A compiler based on the Open64 was developed for the system.Evaluations show that the processor is suitable for high performance applications with a high code density and small program code size.展开更多
针对传统浏览器单线程下载效率低下、过度依赖目标服务器的问题,研究提出了基于HTML5的浏览器端多线程下载技术.基于HTML5 Web Workers技术,实现了浏览器端多线程下载功能;利用分段下载技术,实现了单一文件的多源下载;利用HTML5 File Sy...针对传统浏览器单线程下载效率低下、过度依赖目标服务器的问题,研究提出了基于HTML5的浏览器端多线程下载技术.基于HTML5 Web Workers技术,实现了浏览器端多线程下载功能;利用分段下载技术,实现了单一文件的多源下载;利用HTML5 File System API加Blob对象的技术,实现了浏览器端文件片段的合并功能.实验结果表明,本文提出的方法对于大文件下载,或者高延迟、高丢包率的网络下载环境,效率明显优于单线程下载技术.展开更多
基金Acknowledgements This work was supported by the National High-Tech Research ＆ Development Program of China （863 Program） （2012AA01A301）, and by the National Natural Science Foundation of China （Grant Nos. 61120106005, 61202118, 61303187）.
文摘With the rapid improvement of computation capability in high performance supercomputer system, the imbalance of performance between computation subsystem and storage subsystem has become more and more serious, especially when various big data are produced ranging from tens of gigabytes up to terabytes. To reduce this gap, large-scale storage systems need to be designed and implemented with high performance and scalability. MilkyWay-2 （TH-2） supercomputer system with peak performance 54.9 Props, definitely has this kind of requirement for storage system. This paper mainly introduces the storage system in MilkyWay-2 supercomputer, including the hardware architecture and the parallel file system. The storage system in MilkyWay-2 supercomputer exploits a novel hybrid hierarchy storage architecture to enable high scalability of I/O clients, I/O bandwidth and storage capacity. To fit this architecture, a user level virtualized file system, named H^2FS, is designed and implemented which can cooperate local storage and shared storage together into a dynamic single namespace to optimize I/O performance in IO-intensive applications. The evaluation results show that the storage system in MilkyWay-2 supercomputer can satisfy the critical requirements in large scale supercomputer, such as performance and scalability.
基金Supported by the National Natural Science Foundation of China (No.60236020)the Specialized Research Fund for the Doctoral Program of Higher Education of MOE,China (No.20050003083)
文摘The cost of the central register file and the size of the program code limit the scalability of very long instruction word（VLIW） processors with increasing numbers of functional units.This paper presents the architectural design of a six-way VLIW digital signal processor（DSP） with clustered register files.The architecture uses a variable length instruction set and supports dynamic instruction dispatching.The one-level memory system architecture of the processor includes 16-KB instruction and data caches and 16-KB instruction and data on-chip RAM.A compiler based on the Open64 was developed for the system.Evaluations show that the processor is suitable for high performance applications with a high code density and small program code size.
文摘针对传统浏览器单线程下载效率低下、过度依赖目标服务器的问题,研究提出了基于HTML5的浏览器端多线程下载技术.基于HTML5 Web Workers技术,实现了浏览器端多线程下载功能;利用分段下载技术,实现了单一文件的多源下载;利用HTML5 File System API加Blob对象的技术,实现了浏览器端文件片段的合并功能.实验结果表明,本文提出的方法对于大文件下载,或者高延迟、高丢包率的网络下载环境,效率明显优于单线程下载技术.
