If the traffic is caused by the miss rate from the rim cache, the agent can increase the number of pages to be prefetched in order to improve the rim cache hit rate. However, if the congestion is caused by the cache itself, the agent can decide to clean the cache by removing underutilized pages. To determine if a page should be removed from the cache, the agent can examine its frequency of access over a period of time. The regular prefetching schedule can be organized such that large pages or pages with high distance metric be prefetched during off-peak periods. Access pattern analysis for prefetching The rim cache learns the clients' access pattern and analyzes it for prefetching to minimize latency.
Most structured objects are Web pages.
The weight represents the reference count of the linked object, which increases every time the client accesses the object and decreases periodically with data age. The tree represents the maximum flow at a certain level. The weight of a branch means how often the client will request the object in the future. It executes the prefetching in parallel according to the priority and the current traffic. To avoid the congestion of satellite links by prefetching, the rim and hub cache servers decide whether to prefetch by considering the object's past RTT and time for retrieval.