Distributed caching system

Embodiments of a distributed caching system are disclosed that cache data across multiple computing devices on a network. In one embodiment, a first caching system serves as a caching front-end to a distributed cluster of additional caching systems. The caching systems may be spread over multiple partition groups. In one embodiment, cache writes at a cache system in one partition group are distributed to other partition groups. By propagating the cache writes across multiple partition groups, the caches at the different partition groups include more recently accessed data, thereby increasing the likelihood of cache hits.