Abstract: Regions of data storage involved with fast replication relationships are managed and tracked in order to maintain the integrity of the data on the source and target volumes. In response to a delete operation referencing specified regions of storage, pending fast replication transfers are completed for source regions, fast replication relationships within the specified regions are withdrawn, and the specified regions of storage are release for subsequent allocation and reuse. The present invention facilitates maintaining synchronization of the storage management components of operating systems with the fast replication mechanisms of storage controllers, and releases unused storage regions for subsequent use. A storage subsystem may receive a delete command and make a determination of whether to release the specified regions of storage according to a state of a fast replication relationship with the regions of storage.

Abstract: Methods and apparatus are provided for a current control circuit that forces current sharing among paralleled power converters. Each power converter has an associated current control circuit, which includes a current amplifier and a coupling circuit. The current amplifier outputs a feedback signal to a voltage regulation error amplifier when the power converter output current falls below a predetermined threshold level. The error amplifier causes an increase in the power converter output voltage, forcing an increase in output current. Therefore, each power converter in a paralleled arrangement is regulated to provide a minimum level of output current, based on a predetermined threshold value.

Abstract: A current control circuit forces current sharing among paralleled power converters. Each power converter has an associated current control circuit, which includes a current amplifier and a coupling circuit. The current amplifier outputs a feedback signal to a voltage regulation error amplifier when the power converter output current falls below a predetermined threshold level. The error amplifier causes an increase in the power converter output voltage, forcing an increase in output current. Therefore, each power converter in a paralleled arrangement is regulated to provide a minimum level of output current, based on a predetermined threshold value.