28218
IA-32 Execution Layer: a two-phase dynamic translator designed to support IA-32 applications on Itanium-based systems
IA-32 Execution Layer (IA-32 EL) is a newtechnology that executes IA-32 applications onIntel® Itanium® processor family systems.Currently, support for IA-32 applications onItanium-based platforms is achieved usinghardware circuitry on the Itanium processors.This capability will be enhanced with IA-32EL-software that will ship with Itanium-basedoperating systems and will convert IA-32instructions into Itanium instructions viadynamic translation.In this paper, we describeaspects of the IA-32 Execution Layertechnology, including the general two-phasetranslation architecture and the usage of asingle translator for multiple operatingsystems.The paper provides details of someof the technical challenges such as preciseexception, emulation of FP, MMXTM, and Intel®Streaming SIMD Extension instructions, andmisalignment handling.Finally, the paperpresents some performance results.
15234434
Metadata driven memory optimizations in dynamic binary translator
A dynamic binary translator offers solutions for translating and running source architecture binaries on target architecture at runtime. Regardless of its growing popularity, practical dynamic binary translators usually suffer from the limited optimizations performed when generating the translated code due to the lack of useful information available in the executable files and the requirement to conform to the binary-level compatibility. Trying to generate more efficient translated code, we propose in this paper a novel method of passing performance critical information to a dynamic binary translator through the metadata section generated during the static compilation phase. With the performance critical metadata, the dynamic binary translator is able to perform aggressive optimizations to generate higher quality code. We implemented a general and extensible framework in GCC 4.0 and IA-32® Execution Layer, and selected metadata related to memory optimizations as our target. The metadata enables IA-32 EL to perform memory optimizations such as registerization, memory ordering relaxation and address disambiguation of memory instructions. Experimental data shows an overall performance improvement of 15.03% for SPECfp2000 and 1.21% for SPECint2000. For some specific benchmarks, the performance improvement is even up to 37.09%.
62021419
IA-32 execution layer: a two-phase dynamic translator designed to support IA-32 applications on Itanium/spl reg/-based systems
IA-32 execution layer (IA-32 EL) is a new technology that executes IA-32 applications on Intel Itanium processor family systems. Currently, support for IA-32 applications on Itanium-based platforms is achieved using hardware circuitry on the Itanium processors. This capability will be enhanced with IA-32 EL - software that will ship with Itanium-based operating systems and will convert IA-32 instructions into Itanium instructions via dynamic translation. In this paper, we describe aspects of the IA-32 execution layer technology, including the general two-phase translation architecture and the usage of a single translator for multiple operating systems. The paper provides details of some of the technical challenges such as precise exception, emulation of FP, MMX, and Intel streaming SIMD extension instructions, and misalignment handling. Finally, the paper presents some performance results.
10970909
MAPGrid: A New Architecture for Empowering Mobile Data Placement in Grid Environments
The rising popularity of mobile applications and devices has brought about an enhanced interest in infrastructure support for mobile computing. Our work focuses on the development of a mobile grid infrastructure called MAPGrid (mobile applications on Grids), where grid resources are exploited as proxies to enable advanced mobile applications. However, intermittent availability of grid resources presents challenges for data-intensive mobile applications. In this paper, we propose novel methodologies for placing mobile data on grid proxies. We introduce a notion of two-tier architecture for MAPGrid, where the upper tier captures grid related features and the lower tier represents features associated with mobile environments. We further develop an intelligent mobile data placement mechanism that effectively balances tradeoffs between replication cost and data access cost by leveraging knowledge of grid availability and mobile data request patterns. Through extensive experimentation, we illustrate the superiority of the proposed techniques over several popular data placement strategies.
8929565
Integrating the QMR Method with First Principles Material Science Application Code
First principles methods are used to aid the material designers and metallurgists in the investigation and design of new materials. These methods suffer from a divergent O(N{sup 3}) scaling which restricts the problem sizes that can be addressed. It will be demonstrated that the O(N{sup 3}) scaling problem can be overcome by employing real-space multiple scattering techniques to calculate the scattering properties, combined with the QMR algorithm. By incorporating the QMR method into our real-space multiple scattering code, we observed O(N) scaling for the large problem sizes of interest. This advancement will provide researchers with the necessary tools to treat large systems.
14617194
Effects of Suffix Repetition Rates of a String on the Performance of String Matching Algorithms
The highly efficient Boyer-Moore’s string matching algorithm utilizes information on multi-occurrences of string suffixes in a pattern string to avoid backtracks in searching the pattern string. One hypothesis is that Boyer-Moore’s algorithm even benefits more from highly self-repetitive patterns. In this paper, the author studies how multi-occurrences of string suffixes affect the performance of the Boyer-Moore’s algorithm as well as some other well known string search algorithms. The paper introduces a new concept of suffix repetition rate (SRR) to measure how frequently the suffixes of a string occur inside of the string. Using this measurement, experiments with several thousands patterns over the entire range of SRRs have been carried out, and the results show that increasing of SRR on pattern strings does not improve the performance of a searching algorithm in terms of efficiency.
17669846
Research on the Robustness of a Proportional Integral Switching Surface Based on Sliding Mode Control
In this paper, a novel proportional-integral (PI) switching surface is introduced for determining the synchronization performance of systems in the sliding mode motion. Based on the sliding mode controller, the system is established by a robust control scheme which guarantees the occurrence of a sliding motion of error states even when the parameter uncertainty and external disturbance are present. So this paper researches on robust synchronization problem by investigating a highly complex dynamic nonlinear system—chaotic systems. Some simulation results on controlling different chaotic systems are made and investigated in order to demonstrate the good performance of the method and this control design process is much easier to be completed.
18718248
It is time for a computer application degree
Contemporary computer technology has spread computing activity to almost every field. The computing industry's need for application software developers who have not only proficient programming skills but also a good understanding of subjects in a specific application field has grown rapidly. Continuing to use existing degree programs in computer science to train expected application software developers would not only be a disservice to students but also hamper the further development of computer science programs themselves. Thus, a new degree program is called for in the sub-discipline of computer applications.