A case for application-managed cache for browser

Mobile web usage has significantly increased in last few years. There has been a lot of emphasis on providing good web page performance for mobile devices. Client-side caching can play a significant role in providing good web page performance, but unfortunately, traditional browser caches lack in various aspects leading to sub-optimal performance. More specifically, web applications do not have control on caching, e.g., which resources to cache, how to cache, etc., leading to ineffective cache utilization. Recently, HTML5 has introduced number of persistent storage APIs, that can provide required control for web applications. We evaluate these HTML5 storage options on various devices, and find that they can also meet the performance criteria of caching; in fact, some of the HTML5 storage APIs, e.g., localStorage, can provide even better performance than browser cache. Based on these insights, we make a case for application-managed hierarchical client-side cache, called HCache, that leverages these storage options as backends. We propose a novel API that allows web application developers to intelligently control the caching behavior and the usage of these storage options transparently. Our experiments with a prototype show that HCache can improve web page performance by up to 60%.