This paper presents a novel algorithm to detect null pointer dereference errors. The algorithm utilizes both of the must and may alias information in a compact way to improve the precision of the detection. Using may ...
详细信息
This paper presents a novel Network Request Scheduler (NRS) for a large-scale, LustreTM storage system. It proposes a quantum-based, Object Based Round Robin (OBRR) NRS algorithm that reorders the execution of I/O req...
详细信息
As a typical social media in Web 2.0, blogs have attracted a surge of researches. Unlike the traditional studies, the social networks mined from Internet are very large, which makes a lot of social network analyzing a...
详细信息
ISBN:
(纸本)9781605586762
As a typical social media in Web 2.0, blogs have attracted a surge of researches. Unlike the traditional studies, the social networks mined from Internet are very large, which makes a lot of social network analyzing algorithms to be intractable. According to this phenomenon, this paper addresses the novel problem of efficient social networks analyzing on blogs. This paper turns to account the structural characteristics of real large-scale complex networks, and proposes a novel shortest path approximate algorithm to calculate the distance and shortest path between nodes efficiently. The approximate algorithm then is incorporated with social network analysis algorithms and measurements for large-scale social networks analysis. We illustrate the advantages of the approximate analysis through the centrality measurements and community mining algorithms. The experiments demonstrate the effectiveness of the proposed algorithms on blogs, which indicates the necessity of taking account of the structural characteristics of complex networks when optimizing the analysis algorithms on large-scale social networks. Copyright 2009 ACM.
The Internet-based virtual computing environment (iVCE) provides on-demand aggregation and autonomic collaboration mechanisms to facilitate the utilization of autonomous and dynamic Internet resources. Load balancing ...
详细信息
The Internet-based virtual computing environment (iVCE) provides on-demand aggregation and autonomic collaboration mechanisms to facilitate the utilization of autonomous and dynamic Internet resources. Load balancing and fault tolerance are important issues when scheduling those transient resources. In this paper, we propose a mobility mechanism for the migration of various roles of agents in the iVCE platform. The mobility mechanism involves two parts of the iVCE platform: role container layer and event service layer. At the role container layer, a novel approach is proposed to handle the code and data mobility issue. At the event service layer, an efficient routing reconfiguration protocol is proposed based on a publish/subscribe system over DHTs to facilitate task migrations. Certain conditions must be satisfied before the migration of an agent to ensure the correctness of the whole process. Experiments are conducted to evaluate the performance of the mobility mechanism, and the experimental results show that it is suitable for implementing load balancing and fault tolerance in the iVCE.
Peer-to-peer emerges as a better way for building applications on the Internet that require high scalability and availability. Peer-to-peer systems are usually organized into structured overlay networks, which provide...
详细信息
ISBN:
(纸本)9781605585987
Peer-to-peer emerges as a better way for building applications on the Internet that require high scalability and availability. Peer-to-peer systems are usually organized into structured overlay networks, which provide key-based routing capabilities to eliminate flooding in unstructured ones. Many overlay network protocols have been proposed to organize peers into various topologies with emphasis on different networking properties. However, applications are often stuck to a specific peer-to-peer overlay network implementation, because different overlay implementations usually provide very different interfaces and messaging mechanisms. In this paper, we present a framework for constructing peer-to-peer overlay networks in Java. First, networking is abstracted by the interfaces that use URIs to uniformly address peers on different underlying or overlay networks. Then, asynchronous and synchronous messaging support is built upon these interfaces. Finally, overlay networking interfaces are sketched to handle specific issues in overlay networks. We have constructed several overlay networks in this framework, and built peer-to-peer applications which are independent of overlay implementations. Copyright 2009 ACM.
The power of grid technology in aggregating autonomous resources owned by several organizations into a single virtual system has made it popular in compute-intensive and data-intensive applications. Complex and dynami...
详细信息
The power of grid technology in aggregating autonomous resources owned by several organizations into a single virtual system has made it popular in compute-intensive and data-intensive applications. Complex and dynamic nature of grid makes failure of users' jobs fairly probable. Furthermore, traditional methods for job failure recovery have proven costly and thus a need to shift toward proactive and predictive management strategies is necessary in such systems. In this paper, an innovative effort is made to predict the futurity of jobs submitted to a production grid environment (AuverGrid). By analyzing grid workload traces and extracting patterns describing common failure characteristics, the success or failure status of jobs during 6 months of AuverGrid activity was predicted with around 96% accuracy. The quality of services on grid can be improved by integrating the result of this work into management services like scheduling and monitoring.
The performance of IO-intensive applications is determined by the hit ratio of local disk cache and the IO latency of missed disk accesses. To improve the IO performance, in this paper we propose PIB, a peer-to-peer I...
详细信息
distributed Virtual Environment (DVE) systems have become more and more important both in academic communities and the industries. To guarantee the load constrain, the physical world integrity and the virtual world in...
详细信息
It is found that stable proton acceleration from a thin foil irradiated by a linearly polarized ultraintense laser can be realized for appropriate foil thickness and laser intensity. A dual-peaked electrostatic field,...
详细信息
It is found that stable proton acceleration from a thin foil irradiated by a linearly polarized ultraintense laser can be realized for appropriate foil thickness and laser intensity. A dual-peaked electrostatic field, originating from the oscillating and nonoscillating components of the laser ponderomotive force, is formed around the foil surfaces. This field combines radiation-pressure acceleration and target normal sheath acceleration to produce a single quasimonoenergetic ion bunch. A criterion for this mechanism to be operative is obtained and verified by two-dimensional particle-in-cell simulation. At a laser intensity of ∼5.5×1022 W/cm2, quasimonoenergetic GeV proton bunches are obtained with ∼100 MeV energy spread, less than 4° spatial divergence, and ∼50% energy conversion efficiency from the laser.
Graphics processing units (GPUs) have evolved over the past few years from dedicated graphics rendering devices to powerful parallel processors, outperforming traditional central processing units (CPUs) in many areas ...
详细信息
Graphics processing units (GPUs) have evolved over the past few years from dedicated graphics rendering devices to powerful parallel processors, outperforming traditional central processing units (CPUs) in many areas of scientific computing. The use of GPUs as processing elements was very limited until recently, when the concept of general-purpose computing on graphics processing units (GPGPU) was introduced. GPGPU made possible to exploit the processing power and the memory bandwidth of the GPUs with the use of APIs that hide the GPU hardware from programmers. This paper presents experimental results on the parallelprocessing for some well known on-line string matching algorithms using one such GPU abstraction API, the Compute Unified Device Architecture (CUDA).
暂无评论