Client/server system in which protocol caches for multiple sessions are selectively copied into a common checkpoint cache upon receiving a checkpoint request

摘要

Method, apparatus and program products are provided for persistent cache synchronization for a first communication session and a concurrent second communication session over an external communication link between a client protocol conversion application executing on a first computer and a server protocol conversion application executing on a second computer located remote from the first computer. An active cache is established independently for each session with a corresponding cache for each session at the other computer for use with the first and the second communication session respectively. A checkpoint request is transmitted to the server application indicating one of the active protocol caches from either the first session or the second session to be used to provide a checkpoint. On receipt of the request from the server application, the active protocol cache for the indicated session is copied to provide a checkpoint cache of the second computer. Regardless of which session was indicated, the resulting checkpoint cache of the second computer is associated with both the first and the second session. A checkpoint confirmation message is transmitted to the client application with the first computer responsive to the copying operation. On receipt of the checkpoint confirmation message, the client application creates a checkpoint cache of the first computer as a copy of the indicated one of the first or second sessions protocol cache. The checkpoint cache of the first computer is associated with both the first session and the second session to provide a checkpoint. Operations to create new checkpoints are repeated as desired based upon checkpoint criteria.