Abstract: In a multiple processor transaction processing system, a class response time goal for each class of transactions is enforced by a workload manager, which computes a current average class response time for each transaction class and derives a current class performance index for each of these classes with respect to its class response time goal. Whenever a transaction arrives, the workload manager considers a number of different possible transaction servers to which that arriving transaction could be routed and predicts estimated new values for the class performance indices for each of the considered routing choices. An overall goal satisfaction index is determined for each one and the routing choice corresponding to the best overall goal satisfaction index is selected as the routing choice.

Abstract: A semi-dynamic load balancer for a transaction processing system reallocates transaction types among computers in the system as a group rather than as individual transactions. Statistical data is accumulated in an affinity matrix which records the number of times a transaction type i was blocked by transaction type j was holding a lock on a data item that transaction type i wanted to access. When an overloaded computer is detected, transaction types are reallocated on the computers of the system according to a transaction type routing table which is updated based on data from the affinity matrix.

Abstract: A method and apparatus for coupled computer systems provides a single network node image when connected to a computer network, so that the network is unaware of the "fine" structure of the computer systems in the machine room. The coupled complex is made available to the network.