1. A method, comprising: gathering, by a server, server write activity information at the server to addresses in a storage managed by a storage server on a per page basis for multiple memory pages which are accessed in the server, wherein the storage server caches writes from the server in a write cache; processing the server write activity information to determine a server write activity level comprising one of multiple write activity levels indicating a level of write activity to addresses in the storage by performing: determining a page write activity level for each of the pages being accessed in the server; and processing the page write activity level of each page to determine the server write activity level; and transmitting the determined server write activity level to the storage server, wherein the storage server uses the determined server write activity level to determine whether to adjust a size of the storage server write cache.