Method for synchronizing multiple software caches in a memory

In an information management system, operative on a plurality of networked computer systems and having a central database providing storage of data objects and a plurality of distributed cache management systems, wherein the central database need not be locked, a method for synchronizing cache objects among caches of said plurality of distributed cache management systems comprising:

• providing the plurality of distributed cache management systems with a hierarchical structure;
• processing a client request that either propagates through at least one of the plurality of distributed cache management systems, or the central database, until a response to said client request is issued;
• providing, in said central database, storage for a latest confirmed version of each data object;
• providing that said central database be unlocked upon data access;
• providing through the central database an optimistic control attribute for each data object in the database;
• providing that one distributed cache management system of said plurality of distributed cache management systems is at a top of said hierarchical structure and can communicate with multiple clients;
• changing at each local distributed cache management system each individual cache object when received information impacting the cache object is deemed valid and more current than is contained in a local version of the cache object based on the optimistic control attribute to create a changed version of the cache object;
• and
• causing to be communicated, from a local distributed cache management system to each other local distributed cache management system, the changed version of the cache object without querying the central database, in response to receiving from the central database a central database write confirmation corresponding to the cache object.

A method for synchronizing a transaction in a local cache management system with a central database and a plurality of other distributed cache management systems, the method comprising:

• transmitting a transaction request for the transaction from the local cache management system to said central database;
• receiving an acknowledgement of a status of the transaction from the central database at the local cache management system, wherein said central database need not be locked during the transaction;
• and
• broadcasting the transaction from the local cache management system to said plurality of other distributed cache management systems if said acknowledgement of the status indicates that a central database write of the transaction was successful.

In an information management system, operative on a plurality of networked computer systems, and having a central database providing storage of a latest confirmed version of data objects and a plurality of distributed cache management systems which can communicate with multiple clients, an apparatus for synchronizing cache objects among caches of said plurality of distributed cache management systems, the apparatus comprising:

• means for providing through the central database an optimistic control attribute for each data object in the central database;
• means for changing, at each local distributed cache management system, each individual cache object when received information impacting the cache object is deemed valid and more current than is contained in a local version of the cache object based on the optimistic control attribute, to establish a changed version of the cache object;
• and
• means for causing to be communicated, from a local distributed cache management system to each other local distributed cache management system, the changed version of the cache object without querying the central database, in response to receiving from the central database a central database write confirmation corresponding to the cache object, wherein the central database need not be locked during the central database write.

In an information management system, operative on a plurality of networked computer systems and having a central database providing storage of data objects and a plurality of distributed cache management systems, wherein the central database need not be locked, an apparatus for synchronizing cache objects among caches of said plurality of distributed cache management systems, the apparatus comprising:

• means for providing the plurality of distributed cache management systems with a hierarchical structure;
• means for processing a client request that either propagates through at least one of the plurality of distributed cache management systems, or the central database, until a response to said client request is issued;
• means for providing, in said central database, storage for a latest confirmed version of each data object;
• means for providing that said central database be unlocked upon data access;
• means for providing through the central database an optimistic control attribute for each data object in the database;
• means for providing that one distributed cache management system of said plurality of distributed cache management systems is at a top of said hierarchical structure and can communicate with multiple clients;
• means for changing at each local distributed cache management system each individual cache object when received information impacting the cache object is deemed valid and more current than is contained in a local version of the cache object based on the optimistic control attribute to create a changed version of the cache object;
• and
• means for causing to be communicated, from a local distributed cache management system to each other local distributed cache management system, the changed version of the cache object without querying the central database, in response to receiving from the central database a central database write confirmation corresponding to the cache object.

An apparatus for synchronizing a transaction in a local cache management system with a central database and a plurality of other distributed cache management systems, the apparatus comprising:

• means for transmitting a transaction request for the transaction from the local cache management system to said central database;
• means for receiving an acknowledgement of a status of the transaction from the central database at the local cache management system, wherein said central database need not be locked during the transaction;
• and
• means for broadcasting the transaction from the local cache management system to said plurality of other distributed cache management systems if said acknowledgement of the status indicates that a central database write of the transaction was successful.

A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform a method for, in an information management system, operative on a plurality of networked computer systems, and having a central database providing storage of a latest confirmed version of data objects and a plurality of distributed cache management systems which can communicate with multiple clients, synchronizing cache objects among caches of said plurality of distributed cache management systems, the method comprising:

• providing through the central database an optimistic control attribute for each data object in the central database;
• changing, at each local distributed cache management system, each individual cache object when received information impacting the cache object is deemed valid and more current than is contained in a local version of the cache object based on the optimistic control attribute, to establish a changed version of the cache object;
• and
• causing to be communicated, from a local distributed cache management system to each other local distributed cache management system, the changed version of the cache object without querying the central database, in response to receiving from the central database a central database write confirmation corresponding to the cache object, wherein the central database need not be locked during the central database write.

A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform a method for, in an information management system, operative on a plurality of networked computer systems and having a central database providing storage of data objects and a plurality of distributed cache management systems, wherein the central database need not be locked, synchronizing cache objects among caches of said plurality of distributed cache management systems, the method comprising:

• providing the plurality of distributed cache management systems with a hierarchical structure;
• processing a client request that either propagates through at least one of the plurality of distributed cache management systems, or the central database, until a response to said client request is issued;
• providing, in said central database, storage for a latest confirmed version of each data object;
• providing that said central database be unlocked upon data access;
• providing through the central database an optimistic control attribute for each data object in the database;
• providing that one distributed cache management system of said plurality of distributed cache management systems is at a top of said hierarchical structure and can communicate with multiple clients;
• changing at each local distributed cache management system each individual cache object when received information impacting the cache object is deemed valid and more current than is contained in a local version of the cache object based on the optimistic control attribute to create a changed version of the cache object;
• and
• causing to be communicated, from a local distributed cache management system to each other local distributed cache management system, the changed version of the cache object without querying the central database, in response to receiving from the central database a central database write confirmation corresponding to the cache object.

A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform a method for synchronizing a transaction in a local cache management system with a central database and a plurality of other distributed cache management systems, the method comprising:

• transmitting a transaction request for the transaction from the local cache management system to said central database;
• receiving an acknowledgement of a status of the transaction from the central database at the local cache management system, wherein said central database need not be locked during the transaction;
• and
• broadcasting the transaction from the local cache management system to said plurality of other distributed cache management systems if said acknowledgement of the status indicates that a central database write of the transaction was successful.