Effect Of Cache Size Research Articles

Effect of CPU Cache Size on OpenMP Computing Performance in Fluid-Film Lubrication Analysis

AbstractThe growth of the size of cache and the number of processor cores in modern CPUs is the major factor in advancing the computing performance of modern machines. The effect of CPU cache size in multicore computers on performance, however, has attracted little attention in lubrication and engineering analyses. In this study, the effect of cache size on the computational performance of two parallel iterative methods in solving two Reynolds equations is examined. Four computers, with CPU cache size from 4 to 40 MB and the number of processor cores from 4 to 16, were used. The sizes of the numerical grid were selected to simulate large gridwork (256 × 256) to small gridwork (2048 × 2048) tasks. It is found that the size of CPU cache is a major factor influencing the parallel efficiency in using the RBSOR method. On the other hand, the SPSOR method obtains much higher parallel efficiency than the RBSOR for medium-grained tasks, regardless of the size of CPU cache. The use of the SPSOR can, therefore, provide a much better parallel computing performance than the RBSOR in the cases of having a large number of grids or in a system with limited CPU cache.

Cooperative Data Caching and Prefetching in Wireless Ad Hoc Networks

This article proposes a cooperative data caching and prefetching scheme for Mobile Ad Hoc Networks (MANETs). In this scheme, multiple hosts cooperate in both prefetching and caching commonly used data. To reduce communication and computational overhead, we use a clustering architecture for the network organization. A weak consistency based on time to live value was used to maintain data consistency. A hybrid cache replacement policy that uses frequency of access and the reference time was employed. The effects of cache size, mobility, and prefetching threshold on the network performance were investigated in a discrete event simulation environment. The contribution of intra-cluster and inter-cluster information to overall data accessibility ratio was also investigated. The simulation results indicate that the proposed scheme improves both data accessibility and query delay at relatively lower prefetch thresholds, larger cache sizes, and moderate mobility.

An analytical model for interval caching in interactive video servers

Design of servers to meet the quality of service (QoS) requirements of interactive video-on-demand (VOD) systems is challenging. Recognizing the increasing use of these systems in a wide range of applications, as well as the stringent service demands expected from them, several design alternatives have been proposed to improve server throughput. A buffer management technique, called interval caching, is one such solution which exploits the temporal locality of requests to the same movie and tries to serve requests from the cache, thereby enhancing system throughput. In this paper, we present a comprehensive mathematical model for analyzing the performance of interactive video servers that use interval caching. The model takes into account the representative workload parameters of interactive servers employing interval caching and calculates the expected number of cached streams as an indication of the improvement in server capacity due to interval caching. Especially, user interactions, which sensitively affect the performance of interval caching, are realistically reflected in our model for an accurate analysis. A statistical admission control technique has also been developed based on this model. Using this model as a design tool, we apply the model to measure the impact of different VCR operations on client requests and rejection probability, as well as the effect of cache size.

On filter effects in web caching hierarchies

This article studies the "filter effects" that occur in Web proxy caching hierarchies due to the presence of multiple levels of caches. That is, the presence of one level of cache changes the structural characteristics of the workload presented to the next level of cache, since only the requests that miss in one cache are forwarded to the next cache.Trace-driven simulations, with empirical and synthetic traces, are used to demonstrate the presence and magnitude of the filter effects in a multilevel Web proxy caching hierarchy. Experiments focus on the effects of cache size, cache replacement policy, Zipf slope, and the depth of the Web proxy caching hierarchy.Finally, the article considers novel cache management techniques that can better exploit the changing workload characteristics across a multilevel Web proxy caching hierarchy. Trace-driven simulations are used to evaluate the performance of these approaches. The simulation results demonstrate that size-based partitioning and heterogeneous cache replacement policies each offer improvements in overall caching performance. The sensitivity of the results to the degree of workload overlap among child-level proxy caches is also studied.