Abstract: A method and computer program product for sending a data request from a host bus adapter logic processor to a hard disk drive, setting a standard time out period for receiving a reply from the hard disk drive, sensing vibration in the hard disk drive, sending a vibration alert signal from the hard disk drive to the host bus adapter logic processor in response to the sensed vibration exceeding a predetermined amount of vibration, and, in response to receiving the vibration alert signal from the hard disk drive, the host bus adapter logic processor establishing an extended time out period for receiving the reply. The rotational vibration sensor used by the hard disk drive for repositioning the read/write head may also be used to sense the vibration and form the basis for the vibration alert signal, such as a vibration error code. By extending the time out period during high vibration events, the hard disk drive can ride out the event without being tagged as having failed.

Abstract: Control of the discard of data from cache during backup of the data. In a computer-implemented system comprising primary data storage; cache; backup data storage; and at least one processor, the processor is configured to identify data stored in the primary data storage for backup to the backup data storage, where the identified data is placed in the cache in the form of portions of the data, and where the portions of data are to be backed up from the cache to the backup storage. Upon backup of each portion of the identified data from the cache to the backup storage, the processor marks the backed up portion of the identified data for discard from the cache. Thus, the backed up data is discarded from the cache right away, lessening cache pollution.

Abstract: A mechanism is provided for optimizing and enhancing performance for parity based storage, particularly redundant array of independent disk (RAID) storage. The mechanism optimizes a repetitive pattern write command for performance for storage configurations that require parity calculations. The mechanism eliminates the need for laborious parity calculations that are resource intensive and add to IO latency. For repetitive write commands that span across the full stripe of a RAID5 or similar volume, the mechanism calculates parity by looking at the pattern and the number of columns in the volume. The mechanism may avoid the XOR operation altogether for repetitive pattern write commands. The mechanism may enhance secure delete operations that use repetitive pattern write commands by eliminating data reliability operations like parity generation and writing altogether.

Abstract: A method for increasing the efficiency of a “copy-on-write” operation performed on an SSD to extend the life of the SSD is disclosed herein. In one embodiment, such a method includes receiving a first logical address specifying a logical location where new data should be written to an SSD. The first logical address maps to a first physical location, storing original data, on the SSD. The method further receives a second logical address specifying a logical location where the original data should be available on the SSD. The second logical address maps to a second physical location on the SSD. To efficiently perform the copy-on-write operation, the method writes the new data to a new physical location on the SSD, maps the first logical address to the new physical location, and maps the second logical address to the first physical location. A corresponding apparatus is also disclosed.

Abstract: A method for preserving data availability and I/O performance when creating a virtual RAID volume includes exposing a set of backend virtual volumes. The backend virtual volumes are implemented on a set of physical storage devices (e.g., physical disks or solid state drives) residing on a storage system. The method further enables selection of the set of backend virtual volumes to create a virtual RAID volume having a selected RAID level. The method further provides verification that the backend virtual volumes will be implemented on the physical storage devices in a way that preserves the data availability and I/O performance associated with the selected RAID level.

Abstract: A method for preserving data availability and I/O performance when creating a virtual RAID volume includes exposing a set of backend virtual volumes. The backend virtual volumes are implemented on a set of physical storage devices (e.g., physical disks or solid state drives) residing on a storage system. The method further enables selection of the set of backend virtual volumes to create a virtual RAID volume having a selected RAID level. The method further provides verification that the backend virtual volumes will be implemented on the physical storage devices in a way that preserves the data availability and I/O performance associated with the selected RAID level. A corresponding computer program product and apparatus are also described.

Abstract: An approach to efficient space reclamation in multi-layered thinly provisioned systems. A parent storage volume is thinly provisioned, and uses one or more child storage volumes that are also thinly provisioned for storage. A reclamation command sent to the device providing the parent thinly provisioned storage volume identifies that data has been released, and that the physical storage storing that data can be placed in a free pool and used to satisfy future write requests in the parent storage volume. An identify module identifies which child storage volumes supporting the parent storage volume are thinly provisioned. The data is released at the level of the parent storage volume, and the reclamation command is sent to the child storage volumes supporting the parent storage volume and that are themselves thinly provisioned. The storage is thus released by all affected thinly provisioned storage volumes, and not just the parent storage volume that received the reclamation command.

Abstract: An apparatus and program storage device for maintaining data is provided that includes receiving primary data at a first node, receiving mirrored data from a second and third node at the first node, and mirroring data received at the first node to a second and third node.

Abstract: A method and computer program product for sending a data request from a host bus adapter logic processor to a hard disk drive, setting a standard time out period for receiving a reply from the hard disk drive, sensing vibration in the hard disk drive, sending a vibration alert signal from the hard disk drive to the host bus adapter logic processor in response to the sensed vibration exceeding a predetermined amount of vibration, and, in response to receiving the vibration alert signal from the hard disk drive, the host bus adapter logic processor establishing an extended time out period for receiving the reply. The rotational vibration sensor used by the hard disk drive for repositioning the read/write head may also be used to sense the vibration and form the basis for the vibration alert signal, such as a vibration error code. By extending the time out period during high vibration events, the hard disk drive can ride out the event without being tagged as having failed.

Abstract: A method is disclosed to set the speed of a network. The method supplies a network interconnected with a system controller and a plurality of switch domains, where each of those plurality of switch domains comprises one or more information storage devices and a switch domain controller, and sets by each of the plurality of switch domains a signaling rate for that switch domain. The method queries in-band by the system controller each of the plurality of switch domains for that switch domain's signaling rate, and provides in-band by each of the plurality of switch domains the signaling rate for that switch domain. The method provides in-band by the system controller to each of the plurality of switch domains a first speed selection command specifying a first network speed, and resets by each of the plurality of switch domains the signaling rate for that switch domain to the first network speed.

Abstract: A method to provide an operation to an information storage device is disclosed. The method supplies an information storage device and a protocol conversion device capable of receiving an operation in a first communication protocol comprising a variable attribute, and providing that operation to the information storage device in a second communication protocol, where that second communication protocol does not support the variable attribute. The method provides an operation to the protocol conversion device using said first communication protocol, and determines if the variable attribute is configured in that operation. If the method determines that the variable attribute is not configured in the operation, then the method provides the operation to the information storage device using the second communication protocol.

Abstract: A data storage and retrieval system that comprises a data storage device is disclosed. The data storage and retrieval system further comprises a first LED, a second LED, a third LED, and a fourth LED, interconnected with the data storage device. The data storage device causes the first LED and the second LED to emit first light comprising a first color if the data storage device detects an internal failure. Alternatively, the storage device causes the third LED and the fourth LED to emit second light comprising a second color if the data storage device remains operative.

Abstract: A method for processing a point-in-time copy of data associated with a logical storage volume where the data to be copied is stored in a striped or parallelized fashion across more than one physical source volume. The method includes receiving a point-in-time copy command concerning a logical volume and distributing the point-in-time copy command in-band to each of the physical source volumes containing a portion of the striped data. The method also includes establishing a point-in-time copy relationship between each physical source volume and one of a corresponding set of multiple physical target volumes. The method further includes copying the data stored on each physical source volume to the corresponding physical target volume. The in-band copy command and the striped data may be distributed over I/O channels between a server and the physical storage and processed sequentially.

Abstract: A RAID system is provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a “new data, unconfirmed” state. The state of written data is periodically checked, such as with a timer. If the data is in the “new data, unconfirmed” state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a “single dropped write confirmed” state and the dropped write error is preferably corrected. If no dropped write is detected, the state is changed to a “confirmed good” state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an “unquantifiable” state.

Abstract: A RAID system is provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a “new data, unconfirmed” state. The state of written data is periodically checked, such as with a timer. If the data is in the “new data, unconfirmed” state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a “single dropped write confirmed” state and the dropped write error is preferably corrected. If no dropped write is detected, the state is changed to a “confirmed good” state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an “unquantifiable” state.

Abstract: Methods are provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a “new data, unconfirmed” state. The state of written data is periodically checked, such as with a timer. If the data is in the “new data, unconfirmed” state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a “single dropped write confirmed” state and the dropped write error is preferably corrected. If no dropped write is detected, the state is changed to a “confirmed good” state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an “unquantifiable” state.

Abstract: Method, system and computer program product are provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a “new data, unconfirmed” state. The state of written data is periodically checked, such as with a timer. If the data is in the “new data, unconfirmed” state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a “single dropped write confirmed” state and the dropped write error is preferably corrected. If no dropped write is detected, the state is changed to a “confirmed good” state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an “unquantifiable” state.

Abstract: The distribution of data among a plurality of data storage devices may be optimized, in one embodiment, by redistributing the data to move less-active data to lesser performing data storage devices and to move more-active data to higher performing data storage devices. Power consumption in the datacenter may be optimized by selectively reducing power to data storage devices to which less-active data, such as persistent data, has been moved.

Abstract: A method to supply power to one or more battery-backup assemblies, wherein the method supplies a first controller, a second controller, a first battery-backup assembly, and a second battery-backup assembly. The method further supplies a power bus interconnected to the first controller, the second controller, the first battery-backup assembly, and the second battery-backup assembly, and a first power supply and a second power supply interconnected with the power bus. The method provides power to the first controller and to the second controller and to the first battery-backup assembly over a first period of time, and provides power to the first controller and to the second controller and to the second battery-backup assembly over a second period of time, where the first period of time differs from the second period of time.

Abstract: A method is disclosed to install a component in an information storage and retrieval system. The method provides an information storage and retrieval system comprising a system processor and system data, and a component comprising persistent component data. The method attaches the component to the information storage and retrieval system while the information storage and retrieval system remains in normal operation, and determines, while the information storage and retrieval system remains in normal operation, if the component is compatible with the information storage and retrieval system. If the component is compatible with the information storage and retrieval system, the method then places the component into service while the information storage and retrieval system remains in normal operation.