Design And Implementation Of The Optimization Mechanism In Prepress Review System

The Prepress Review System is the network printing system that kodak has provided for print manufacturers since 2000.The main purpose of the system is to review the pending print before it is formally printed.The system resolve the problems of process irregularities,management confusion,and inadequate mechanisms in the review process and it has reacted well in the printing market.However,as the number of users increased and the functional requirements changed,the existing prepress review system gradually revealed some disadvantages.First,high concurrency cannot be supported.The original prepress review system using single server provides web service,so it can't support a growing number of users of high concurrent requests,led to the long time of the system response,low task processing efficiency,and even a large number of requests can't be responsed.Second,function extensing are complex.As the business evolves,the system needs to extend its function.Due to the typical prepress review system based on RPC style,it must change the 4 layer related protocol stack when extending web service,leading to the complication of expansing the function.There are two problem that the prepress review system needs to solve.In order to solve these two problems,A optimization mechanism is designed and implemented in this paper.Considering high concurrency problem,This thesis design load balancing optimization of the prepress review system.A new load balancing policy is designed based on apache load balancing mechanism.Considering extending function problem,This thesis design a restful web service in prepress review system.This thesis design and implement a set of rest-architecture style web services which combine well with the load balance cluster.Considering the implementation of system functions,the Apache mod_proxy module is extended and the REST API module is implemented in order to accomplish the load balancing policy and restful web service.Finally,this thesis use stress testing software which are installed on more than one client conducting stress tests,comparing with the original system,verifing the effect of the optimization mechanism.The optimized prepress review system increases the concurrency of the system compared to the unoptimized prepress review system.It can increase the number of users and generate economic benefits for the company.For software engineers,When the function expands,it also reduces the amount of work so the product rollout can be more fast and iterative.