Abstract: Provided are a method, system, and program for consolidating session information for a cluster of sessions in a coupled session environment. Information for each of a plurality of sessions comprising a cluster is stored in a memory of a processor session. Each session associates at least one primary system and at least one secondary system, wherein within each session, updates are copied from the at least one primary system to the at least one secondary system. The session information in the memory for the plurality of sessions is processed to generate consolidated session information for the cluster based on the session information for the sessions in the cluster. The consolidated session information for the cluster is written to a master data set maintaining information for sessions.

Abstract: Provided are a method, system, and program for consolidating session information for a cluster of sessions in a coupled session environment. Information for each of a plurality of sessions comprising a cluster is stored in a memory of a processor session. Each session associates at least one primary system and at least one secondary system, wherein within each session, updates are copied from the at least one primary system to the at least one secondary system. The session information in the memory for the plurality of sessions is processed to generate consolidated session information for the cluster based on the session information for the sessions in the cluster. The consolidated session information for the cluster is written to a master data set maintaining information for sessions.

Abstract: Provided are a method, system, and program for consolidating session information for a cluster of sessions in a coupled session environment. Information for each of a plurality of sessions comprising a cluster is stored in a memory of a processor session. Each session associates at least one primary system and at least one secondary system, wherein within each session, updates are copied from the at least one primary system to the at least one secondary system. The session information in the memory for the plurality of sessions is processed to generate consolidated session information for the cluster based on the session information for the sessions in the cluster. The consolidated session information for the cluster is written to a master data set maintaining information for sessions.

Abstract: Disclosed is an article of manufacture, system, and program for determining device suspension and device blocking. Local session cache usage and residual counts are compared against limit values associated with that session, wherein the limit values comprise a device blocking count, a device blocking percent, a suspend count, and a suspend percent for the local session. If a cache in trouble condition is detected based on the comparison, the cache in trouble condition is processed to determine whether one or more volumes are to be blocked or suspended.

Abstract: Disclosed is an article of manufacture, system, and program for determining device suspension and device blocking. Local session cache usage and residual counts are compared against limit values associated with that session, wherein the limit values comprise a device blocking count, a device blocking percent, a suspend count, and a suspend percent for the local session. If a cache in trouble condition is detected based on the comparison, the cache in trouble condition is processed to determine whether one or more volumes are to be blocked or suspended.

Abstract: A method, apparatus, and article of manufacture for performing a point-in-time backup using a snapshot function. Work space on a work virtual volume is obtained to hold the snapshot copy of the source data being copied from a source virtual volume. Updates to the source virtual volume are suspended during the snapshot function, so as to provide a logically consistent view of the source virtual volume at a common point in time. Pointers are copied from a virtual track table of the source virtual volume to a virtual track table of the work virtual volume without actually moving any data on data storage devices referenced by those pointers. As a result, the snapshot function provides a method for copying the source virtual volume to the work virtual volume very quickly. Upon completion of the snapshot function, updates to the source virtual volume may be resumed.

Abstract: Data is stored in one or more data storage devices, the number of active data storage devices being adaptively adjusted to maximize parallelism while minimizing device overhead. Multiple datasets are first received, these being designated for storage in multiple data storage devices. Next, a first one of the received datasets is stored in a first one of the data storage devices. Concurrently with storage of the first dataset, the following steps are performed: (1) selecting a second received dataset from those remaining to be stored, (2) selecting an available data storage device by employing a predetermined criteria, and (3) beginning storage of the second dataset in the selected data storage device. The predetermined criteria for selecting an available data storage device may involve, for example, selecting an available device based on a "first fit" or a "best fit" scheme. Concurrently with storage of the second dataset, storage of a third dataset starts.