More and more embedded devices,such as mobile phones,tablet PCs and laptops,are used in every field,so huge files need to be stored or backed up into cloud storage.Optimizing the performance of cloud storage is very important for Intet development.This paper presents the performance evaluation of the open source distributed storage system,a highly available,distributed,eventually consistent object/blob store from OpenStack cloud computing components.This paper mainly focuses on the mechanism of cloud storage as well as the optimization methods to process different sized flies.This work provides two major contributions through comprehensive performance evaluations.First,it provides different configurations for OpenStack Swift system and an analysis of how every component affects the performance.Second,it presents the detailed optimization methods to improve the performance in processing different sized files.The experimental results show that our method improves the performance and thestructure.We give the methods to optimize the object-based cloud storage system to deploy the readily available storage system.