Prioritized transaction server allocation

A computer-readable medium whose contents cause a computer system to distribute transaction servers to process transactions of a plurality of different types, the transaction types being organized into a plurality of priority levels ordered from highest to lowest, each priority level having one or more transaction types, each transaction type further having a service level goal reflecting the level of service sought for transactions of the transaction type, by performing the steps of:

• identifying transaction servers when they become available to process transactions;
• for each identified transaction server, in response to the identification of the transaction server:
• for each priority level, from the highest priority level to the lowest priority level, until the identified transaction server is assigned to process a transaction of a selected type:
• determining whether assigning the identified transaction server to a transaction of any of the transaction types of the priority level is necessary to meet the service level goal for that transaction type;
• if it is determined that assigning the identified transaction server to a transaction of any of the transaction types of the priority level is necessary to meet the service level goal for that transaction type, assigning the identified transaction server to process a transaction of one of the transaction types of the priority level;
• and
• after the assigned transaction server has completed processing of the transaction to which it was assigned, reidentifying the assigned transaction server as being available to process transactions.

An apparatus for distributing transaction servers to process transactions of a plurality of different types, the transaction types being organized into a plurality of priority levels ordered from highest to lowest, each priority level having one or more transaction types, the apparatus comprising:

• a service level goal attribution subsystem for attributing a service level goal to each transaction type that reflects the level of service sought for transactions of this type;
• an identification subsystem that identifies transaction servers when they become available to process transactions;
• and
• a transaction server distribution subsystem that, in response to each transaction server identification by the identification subsystem, assigns the identified transaction server to process a transaction of a type that needs an additional transaction server to meet its service level goal, and whose priority level is at least as high as that of any other transaction type that needs an additional transaction server to meet its service level goal,
• the identification subsystem reidentifying assigned transaction servers when they complete processing of the transactions to which they were assigned.

A computer memory containing a transaction server allocation data structure usable to allocate an available transaction server to processing one of a plurality of transaction types, the data structure comprising, for each transaction type:

• an indication of the priority of transactions of the transaction type relative to the priorities of transactions of other transaction types;
• and
• an indication of a service level goal reflecting the level of service sought for transactions of the transaction type,
• such that the data structure may be used to allocate an available transaction server by, for each transaction type, in descending order of the priorities indicated for the transactions of the transaction types, determining whether the available transaction server is needed in order to meet the service level goal indicated for the transaction type, and assigning the available transaction server to the highest priority transaction type for which the available transaction server is determined to be needed.

A method in a computer system for distributing available transaction servers among a plurality of transaction processing applications each having the same priority, each application further having a service level goal indicating the service level sought for the application, the method comprising the steps of, when a transaction server becomes available:

• establishing an order for the applications, from highest to lowest;
• for each application, in the established order, until the available transaction server is assigned to an application;
• offering the available transaction server to the application;
• under the control of the application, determining whether the available transaction server is needed by the application in order for the application to meet its service level goal;
• and
• if it is determined that the available transaction server is needed by the application in order for the application to meet its service level goal, assigning the available transaction server to the application,
• such that each available transaction server is assigned to the application that is highest in the established order that needs the available transaction server in order to meet its service goal.

A computer-readable medium whose contents cause a computer system to distribute available transaction servers among a plurality of transaction processing applications each having the same priority, each application further having a service level goal indicating the service level sought for the application, by performing the steps of, when a transaction server becomes available:

• establishing an order for the applications, from highest to lowest;
• for each application, in the established order, until the available transaction server is assigned to an application;
• offering the available transaction server to the application;
• under the control of the application, determining whether the available transaction server is needed by the application in order for the application to meet its service level goal;
• and
• if it is determined that the available transaction server is needed by the application in order for the application to meet its service level goal, assigning the available transaction server to the application.

A method in a computer system for maintaining a target service level of a transaction processing application that uses reassignable transaction servers to process transactions that arrive from a transaction source, the method comprising the steps of:

• receiving an offer of an additional transaction server;
• determining the rate at which transactions are arriving from the transaction source;
• determining the number of transactions that have arrived from the transaction source whose processing has not been assigned to a transaction server;
• determining the rate at which processing of transactions is being completed;
• and
• based on the target service level, the determined rate at which transactions are arriving from the transaction source, the determined number of transactions that have arrived from the transaction source whose processing has not been assigned to a transaction server, and the rate at which processing of transactions is being completed, determining whether the offered additional transaction server is needed to satisfy the target service level;
• and
• accepting the offered additional transaction server to enable the offered additional transaction server to be assigned to a transaction of the application only if it is determined that the offered additional transaction server is needed to satisfy the target service level.

A computer-readable medium whose contents cause a computer system to maintain a target service level of a transaction processing application that uses reassignable transaction servers to process transactions that arrive from a transaction source by performing the steps of:

• receiving an offer of an additional transaction server;
• determining the rate at which transactions are arriving from the transaction source;
• determining the number of transactions that have arrived from the transaction source whose processing has not been assigned to a transaction server;
• determining the rate at which processing of transactions is being completed;
• and
• based on the target service level, the rate at which transactions are arriving from the transaction source, the determined number of transactions that have arrived from the transaction source whose processing has not been assigned to a transaction server, and the determined rate at which processing of transactions is being completed, determining whether the offered transaction server is needed to satisfy the target service level;
• and
• accepting the offer only if it is determined that the offered transaction server is needed to satisfy the service level.

A method in a computer system for maintaining a target service level of a transaction processing application that uses reassignable transaction servers to process transactions that arrive from a transaction source, the method comprising the steps of:

• receiving an offer of an additional transaction server;
• determining a current service level reflecting the current transaction processing performance of the application;
• comparing the determined current service level to the service level goal;
• and
• based on the result of the comparing step, determining whether the offered transaction server is needed to satisfy the service level goal;
• and
• accepting the offer only if it is determined that the offered transaction server is needed to satisfy the service level goal.

A method in a computer system for distributing reassignable transaction processing servers among a plurality of transaction processing applications, the method comprising the steps of:

• defining for a first application of the plurality a transaction assignment service level goal reflecting the performance sought for the first application in assigning transactions to a server;
• defining for a second application of the plurality a transaction completion service level goal reflecting the performance sought for the second application in completing the processing transactions;
• when a server is available for distribution:
• assessing the demand for an additional server by the first application based on the transaction assignment service level goal defined for the first application;
• assessing the demand for an additional server by the second application based on the transaction completion service level goal defined for the second application;
• comparing the assessments;
• and
• based upon the results of the comparing step, selecting between the first and second application for distribution of the available server.

A computer-readable medium whose contents cause a computer system to distribute reassignable transaction processing servers among a plurality of transaction processing applications by performing the steps of:

• defining for a first application of the plurality a transaction assignment service level goal;
• defining for a second application of the plurality a transaction completion service level goal;
• when a server is available for distribution:
• assessing the demand for an additional server by the first application based on the transaction assignment service level goal defined for the first application;
• assessing the demand for an additional server by the second application based on the transaction completion service level goal defined for the second application;
• comparing the assessments;
• and
• based upon the results of the comparing step, selecting between the first and second application for distribution of the available server.