Caching infrastructure

A method for retrieval of presence metadata, the method comprising:nreceiving a request from a first client to edit a document file;sending short-term check out metadata to the first client to begin an editing session; andwriting a transition ID to a transition table stored in a cache, wherein the presence of another transition ID in the cache indicates that a document has switched from a single-client mode to a multi-client mode.

A system including a cache infrastructure for retrieval of presence metadata,the system comprising:na memory storage unit; anda processing unit coupled to the memory storage unit, wherein the processing unit is operative to:nreceive short-term check out metadata from a first client to begin an editing session for a document;add a transition ID to the short-term check out metadata;write the transition ID to a transition table stored in a cache,switch from a single-client mode to a multi-client mode, wherein switching from the single-client mode to the multi-client mode comprises the processing unit being operative to notice when the first client attempts to take another short-term lock on the document and seeing that that a second client has already received the document;determine if the multi-client mode is in progress by checking a database;receive a ping from the first client to determine if the transition ID is in the cache;if the transition ID is not in the cache,nreceive pings from the first client at regular intervals, andsave the document to a server a plurality of times without incurring any reads/writes to the database, andif the transition ID is in the cache,nreceive a ping from the first client to collect a lock table from the database to identify the second client, andreceive the second client's lock information by receiving pings that do not carry lock information.

A client computer for retrieval of metadata relating to a multi-client editing session, the client computer comprising:na memory unit; anda processing unit operative to:nreceive a document from a storage device, the document comprising short-term check out metadata indicating an editing session has begun;ping a cache to determine if another transition ID is stored in the cache; andsend a transition ID to a transition table stored in a cache if the another transition ID is not stored in the cache to switch from a single-client mode to a multi-client mode.