Cache Refreshing for Online Social Newsfeeds

A computer-readable storage medium persistently storing a program, wherein the program, when executed, instructs a processor to perform the following operations:

• receive a request for a newsfeed from a user of an online social service, wherein the newsfeed depends at least in part on a memory-cached list of social friends of the user and on a memory-cached list of events associated with each social friend;
• refresh a memory-cached copy of the list of social friends from a corresponding list in a persistent data store, based upon a determination of a utility associated with the user;
• refresh a memory-cached copy of a list of events associated with a social friend from a corresponding list of events in a persistent data store, based upon a determination of a utility associated with the social friend;
• and
• cause the newsfeed to be displayed to the user,

A method, comprising the operations of:

• receiving a request for a newsfeed from a user of an online social service, wherein the newsfeed depends at least in part on a memory-cached list of social friends of the user and on a memory-cached list of events associated with each social friend;
• refreshing a memory-cached copy of the list of social friends from a corresponding list in a persistent data store, based at least in part on a rate of addition of friends by the user and a rate of removal of friends by the user;
• refreshing a memory-cached copy of a list of events associated with a social friend from a corresponding list of events in a persistent data store, based at least in part on a rate of generation of events by the social friend;
• and
• causing the newsfeed to be displayed to the user, wherein each of the rates is periodically updated an each operation of the method is executed by one or more processors.