Abstract: Nested recovery scope management systems and methods for a multiple process computer system having a dynamic multiple address space server are disclosed. Stateless recovery agents are employed, under the control of a supervisory program called Recovery Director, during initialization or restart of servers to restore recoverable data in response to identified failures or other abnormal termination. The Director controls the recovery of protected resources in a systematic manner. The Director is initialized when a first address space of a first server is started. Then, as each instance of a recoverable component is initialized, the component registers with the Director by providing a reference to a stateless recovery agent that can later perform recovery functions for it if needed. As part of the registration, a token representing the current failure scope of the registration is generated and provided to the recoverable component by the Director.

Abstract: A histogram, or resource status history table, for multiple resources is created and maintained. A transaction or resource manager arranges and/or reorders various resources into a sequence based on the histogram such that read-only resources are prepared first and a sole non-read-only resource need not be prepared, but only committed. The transaction manager heuristically determines the order that resources are driven to achieve last-agent optimization. The histogram is kept related to context, based on runtime and applications context to ensure that usage patterns by context are optimized without the need for the installation to know any usage patterns.

Abstract: Indoubt transaction entries are recorded for each member of a database cluster, thereby avoiding the CPU cost and elapsed-time impact of persisting this information to a disk (either via a log write or a relational table I/O). This implementation allows for full read/write access and data coherency for concurrent access by all the members in the database cluster. At any given point in time, a full list of indoubt transactions is maintained for the entire database cluster in a relational table (e.g., an SQL table).

Abstract: An apparatus includes a browse mechanism to scan a list of data items. A marker is applied to the data items once they have been scanned by the browse mechanism. The marker provides an indication that a respective data item has been scanned by a given browse entity. The browse mechanism subsequently scans only unmarked data items in the list of data items.