The Design And Implementation Of Preemptive Scheduling Subsystem In LSF System

This paper optimizing the existing preemptive sheduling module under the existting grid system . It solves the waste of resource which was caused by the calloc resource phase through preemptive process. It realizes the purpose of mimizing the waste of the resource. Through this way, it will impove the utilization of resource and improve efficiency of the system.The original subsystem in LSF only cares about the performance without optimizing the functionality of the subsystem. Thus the subsystem will cause certain waste of resource when preemptive happenes. This paper design and implement the preemptive sheduling subsysem in order to fullfill the requirement of both functionality and performance. And user can tradeoff the functionality and performance throught some arguments.This paper bases on the real requiremen of the user. First, it analyzes the current research on preemptive scheduling to determine the scope and the contetnt of this paper. Second, this paper analyzes the requirement according to the requiremnt of the user. It analyzes the main architecture and the algorithm needed. The requirement including the module partition and the requirement of each module. Third, this paper design some data structure for the subsysem, implement the incremental search and enhanced quick search algorithm to make sure users can get the satisfied result in most situation. This paper design and implement and initial module, data collect and tranfer module and job status maintanance module to reduce the interaction between the modules. With this design, the subsystem has a very good compatibility and it is very easy for the developer to add new functionality. Finally, this paper compares the new design subsystem with the old subsystem in both functionality and performace. It proves that the new subsystem can fullfill the functionality under the performance constraint of the original system.Through the new preemptive scheduling algorithm and a few other auxiliary functions in cooperation with the module, the waste rate of the subsystem reduces from 0.13 to 0.01. And the time increase from 0.254 second to 0.268 second, which can fullfill the time constraint of the scheduling. Thereby the new feature is success.