Showing papers by "Sanjeev Setia published in 1994"

Analysis of processor allocation in multiprogrammed, distributed-memory parallel processing systems

Abstract: A main objective of scheduling independent jobs composed of multiple sequential tasks in shared-memory and distributed-memory multiprocessor computer systems is the assignment of these tasks to processors in a manner that ensures efficient operation of the system. Achieving this objective requires the analysis of a fundamental tradeoff between maximizing parallel execution, suggesting that the tasks of a job be spread across all system processors, and minimizing synchronization and communication overheads, suggesting that the job's tasks be executed on a single processor. The authors consider a class of scheduling policies that represent the essential aspects of this processor allocation tradeoff, and model the system as a distributed fork-join queueing system. They derive an approximation for the expected job response time, which includes the important effects of various parallel processing overheads (such as task synchronization and communication) induced by the processor allocation policy. >

Optimal write batch size in log-structured file systems

Abstract: Log-structured file systems create a performance benefit by maximizing the rate at which disk write operations can occur. However, this benefit comes at the expense of individual read operations, which can experience long queuing delays due to batched write service. This paper presents an ana- lytic derivation of the write batch size that minimizes read response time, while retaining the benefit of write batching. Simulations that relax the assumptions of the analytic model demonstrate that the analytic result can be used to advantage in a practical setting.