International Business Machines Corporation

Kevin C Lin

Theresa Mary Brown

Gregory E McBride

Carol Santich Mellgren

Nicolas Marc Clayton

Nedlaya Yazzie Francisco

Matthew Sanchez

Theodore Timothy Harris, Jr

Eric Francis Robinson

Raul Eduardo Saba

Jason Alan Cox

David Fei

Karl Allen Nielsen

Gail Andrea Spear

Clint Alan Hardy

Mark L Lipets

Omer Heymann

Mark J Wolski

Nadav Levison

Dave Fei

Provided are techniques for performing a recovery copy command to restore a safeguarded copy backup to a production volume. In response to receiving a recovery copy command, a production target data structure is created. A read operation is received for data for a storage location. In response to determining that the data for the storage location is in a cache of a host and a generation number is greater than a recovery generation number, the data is read from the cache. In response to determining at least one of that the data for the storage location is not in the cache and that the generation number is not greater than the recovery generation number, the data is read from one of the production volume and a backup volume based on a value of an indicator for the storage location in the production target data structure.

Performing a recovery copy command to restore a safeguarded copy backup to a production volume

Consistency groups are asynchronously copied to a remote computational device, from a local computational device, wherein point in time copy operations are performed at the local computational device while the consistency groups are being asynchronously copied to the remote computational device. Indicators are stored at the remote computational device to identify those point in time copy operations that are to be restored as part of a recovery operation performed at the remote computational device in response to a failure of the local computational device.

Restoration of data when point in time copy operations are performed during asynchronous copy

Provided are a computer program product, system, and method for copying point-in-time data in a storage to a point-in-time copy data location in advance of destaging data to the storage. A point-in-time copy is created to maintain tracks in a source storage unit as of a point-in-time. A source copy data structure indicates tracks in the source storage unit to copy from the storage to a point-in-time data location. An update to write to a source track is received and a determination is made as to whether the source copy data structure indicates to copy the source track from the storage to the point-in-time data location. The update is written to a cache. A copy operation is initiated to copy the source track from the storage to the point-in-time data location asynchronous before the source track is destaged from the cache to the storage unit.

Copying point-in-time data in a storage to a point-in-time copy data location in advance of destaging data to the storage

A plurality of tracks that are to be copied to a backup volume are aggregated in a container data structure. The plurality of tracks are stored physically contiguously in a single Redundant Array of Independent Disks (RAID) stride. Mapping metadata is updated in the backup volume to indicate how logical tracks of the backup volume correspond to physical tracks stored in the RAID stride.

Aggregation of updated tracks to be copied to a backup volume for physically contiguous storage on a RAID stride

A method, system and computer-usable medium are disclosed for improved point-in-time copying of data within an asynchronous data mirroring environment comprising: receiving a request to initiate an asynchronous data mirroring operation associated with a first point-in-time copying process; processing a first set of establish data to generate a point-in-time establish reservation, the first set of establish data associated with the first point-in-time copying process establish; using the point-in-time establish reservation to generate a second set of establish data if the second point-in-time copying process can be performed; using the second set of establish data to initiate a second point-in-time copying process; and, tracking establish operations in progress between the first point-in-time copying process and the second point-in-time copying process.

Coordination of point-in-time copy in asynchronous mirror environment during consistency group formation

Acquiring access to a token controlled system resource, including: receiving, by a token broker, a command that requires access to the token controlled system resource, where the token broker is automated computing machinery for acquiring tokens and distributing the command to the token controlled system resource for execution; identifying, by the token broker, a first need state, the first need state indicating that the token broker requires access to the token controlled system resource to which the token broker does not possess a token; requesting, by the token broker, a configurable number of tokens to gain access to the token controlled system resource, without dispatching an operation handler for executing the command until at least one token is acquired; assigning, by the token broker, an acquired token to the operation handler; and dispatching, by the token broker, the operation handler and its assigned token for executing the command.

Acquiring access to a token controlled system resource

Methods and apparatuses are disclosed for direct access to cache memory. Embodiments include receiving, by a direct access manager that is coupled to a cache controller for a cache memory, a region scope zero command describing a region scope zero operation to be performed on the cache memory; in response to receiving the region scope zero command, generating a direct memory access region scope zero command, the direct memory access region scope zero command having an operation code and an identification of the physical addresses of the cache memory on which the operation is to be performed; sending the direct memory access region scope zero command to the cache controller for the cache memory; and performing, by the cache controller, the direct memory access region scope zero operation in dependence upon the operation code and the identification of the physical addresses of the cache memory.

Direct access to cache memory

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Raleigh, NC, United States of America

Kevin C Lin