As the World Wide Web becomes more popular and more sophisticated, the roles of many web caches are getting more critical to the performance of the entire web. One of the major performance bottlenecks of web caches is the access delay of disks. Web caches have relatively simple but very intensive disk jobs, and the conventional file systems are not efficient in the environment of web caches’ unique disk workloads. In this thesis, a disk management scheme based on multiple-size blocks for web caches is proposed. This scheme can boost up the web caches’ disk performance by optimizing in the consideration of the web caches’ unique environment, especially by simplifying the block reallocation procedure during the cache replacement. To evaluate our system’s superiority to the existing approach, the performance comparison is performed by experiments based on the input workload from the real web caches’ traces. Our system shows approaximately 30% performance enhancement over the existing solution.