Abstract: Methods and systems for data reconstruction following drive failures may include: storing data across two or more drives in one or more data stripes, each data stripe including two or more drive extents; detecting a degradation of a drive containing a drive extent associated with a first data stripe; assigning a reconstruction priority to the drive extent associated with the first data stripe; detecting a degradation of a drive containing a drive extent associated with a second data stripe; and assigning a reconstruction priority to the drive extent associated with the second data stripe.

Abstract: The present invention is a system and method which allows for a VTL system that supports thin provisioning to implicitly unmap unused storage. Such unmap operations may occur even though the VTL system does not receive any explicit unmap requests from its initiators. For example, if a system administrator knows that once a virtual tape drive of the VTL system has been partially overwritten, all previously written data sets on that virtual tape drive will never again be accessed, the system administrator may configure the VTL system so that it unmaps the entire remainder of the virtual tape drive on the first data overwrite.

Abstract: The present disclosure is directed to a system and a method for optimizing redundancy restoration in distributed data layout environments. The system may include a plurality of storage devices configured for providing data storage. The system may include a prioritization module communicatively coupled to the plurality of storage devices. The prioritization module may be configured for determining a restoration order of at least a first data portion and a second data portion when a critical data failure occurs. The system may include a restoration module communicatively coupled to the plurality of storage devices and the prioritization module, the restoration module configured for restoring at least the first data portion and the second data portion based upon the restoration order.

Abstract: The present invention is a method for utilizing mirroring in a data storage system to promote improved data accessibility and improved system efficiency. The method includes establishing a first set of drives of the system in active mode and a second set of drives of the system in passive mode (ex.—a lower power mode). The method further includes writing a first portion of data to a first drive of the first drive set, and writing a copy of the first portion of data to a second drive of the first drive set. A third drive (ex.—from the second drive set), may be activated from passive mode to active mode. The method may further include writing a second copy of the first data portion to the third drive, re-establishing the third drive in passive mode, and deleting the copy of the first data portion from the second drive.

Abstract: The present invention is a method for drive management and data placement in an archival storage system having a set of drives. The method includes mapping redundant data stripes onto the drives. A first active data stripe, located on a first subset of the drives, is then selected from the mapped data stripes. The first subset is placed into a normal power state and a second subset of the drives is placed into a low power state. Data is then written to the first active data stripe. Before the first active data stripe is fully used, the method includes selecting a next active/second active data stripe from the mapped data stripes, the second active data stripe being at least partially located on the second subset. The method may be performed by a system which implements MAID techniques for drive management and CRUSH for data placement.

Abstract: A set of data is allocated into a plurality of data chunks, wherein the plurality of data chunks is thinly provisioned and erasure coded. A plurality of storage devices is divided into a first and a second set of storage devices, wherein the first set of storage devices is powered up and the second set of storage devices is powered down. The data chunks are distributed on the first set of storage devices to equally load each of the first set of storage devices. A storage device from the second set of storage devices is powered up to reassign the storage device from the second set of storage devices to the first set of storage devices. Data chunks are migrated to a reassigned storage device until the data chunks are evenly distributed on the first set of storage devices and the reassigned storage device.

Abstract: The present invention is a system for optimizing the reconstruction and copyback of data contained on a failed disk in a multi-disk mass storage system. A system in accordance with the present invention may comprise the following: a processing unit requiring mass-storage; one or more disks configured as a RAID system; an associated global hot spare disk; and interconnections linking the processing unit, the RAID and the global hot spare disk. In a further aspect of the present invention, a method for the reconstruction and copyback of a disconnected RAID disk utilizing a global hot spare disk is disclosed. The method includes: disconnecting a RAID component disk; reconstructing data from the disconnected RAID disk onto a global hot spare disk; reconnecting the disconnected RAID component disk; and copying the reconstructed data from the global hot spare disk back to the reconnected RAID component disk.

Abstract: The present invention is a system for optimizing the reconstruction and copyback of data contained on a failed disk in a multi-disk mass storage system. A system in accordance with the present invention may comprise the following: a processing unit requiring mass-storage; one or more disks configured as a RAID system; an associated global hot spare disk; and interconnections linking the processing unit, the RAID and the global hot spare disk. In a further aspect of the present invention, a method for the reconstruction and copyback of a failed disk volume utilizing a global hot spare disk is disclosed.

Abstract: The present invention is a system for optimizing the reconstruction and copyback of data contained on a failed disk in a multi-disk mass storage system. A system in accordance with the present invention may comprise the following: a processing unit requiring mass-storage; one or more disks configured as a RAID system; an associated global hot spare disk; and interconnections linking the processing unit, the RAID and the global hot spare disk. In a further aspect of the present invention, a method for the reconstruction and copyback of a disconnected RAID disk utilizing a global hot spare disk is disclosed. The method includes: disconnecting a RAID component disk; reconstructing data from the disconnected RAID disk onto a global hot spare disk; reconnecting the disconnected RAID component disk; and copying the reconstructed data from the global hot spare disk back to the reconnected RAID component disk.

Abstract: A method for configuring a computer network that includes a full duplex bi-directional first port and an initiator that can issue a request for the first port to assume a state. The first port, when in a first state, is able to bi-directionally communicate with a full duplex bi-directional second port, and when in a second state, is coupled to itself by having an output thereof coupled to an input thereof. The method comprises inhibiting the initiator from issuing the request, sending data to the initiator describing a desired state of the first port, and enabling the initiator to issue the request for the first port to assume the desired state.