Abstract: A method includes distributively encoding data stored in a storage system using an erasure-correcting code. The encoded data is distributed into multiple w storage device arrays in the storage system. Each storage device array includes n storage devices. Each storage device is divided into m sectors or pages. The n storage devices are grouped into l groups of t storage devices each. Data erasures in the w storage device arrays are corrected by recovering erased data using the erasure-correcting code of un-erased data based on each row and column in each m×n array being protected by the erasure-correcting code for the data. Each group of t storage devices contains extra second responder parities to correct extra data erasures in addition to data erasures corrected by first responder vertical parities in each m×t subarray, and w, n, m, l and t are positive integers.

Abstract: One embodiment provides a system including a computer processor, a computer-readable hardware storage device, and program code embodied with the computer-readable hardware storage device for execution by the computer processor to implement a method that includes selecting a first blob for reclamation from a first data center. The first blob includes multiple erasure code groups. A first message is sent to a second data center indicating the first blob is to be reclaimed. A second message is sent to the second data center after reclaiming the first blob in the first data center. A global reclamation complete message is received from the second data center. The global reclamation complete message indicates a second blob in the second data center has been reclaimed. The global reclamation complete message is sent in response to the second data center receiving a local reclamation complete message from a third data center.

Abstract: One embodiment provides a method for reclaiming free space. The method comprises selecting a first blob for reclamation from a first data center; sending a first message to a second data center indicating the first blob is to be reclaimed; sending a second message to the second data center after reclaiming the first blob; receiving a global reclamation complete message from the second data center; reading at least one data set from the first blob; and storing in a write buffer the at least one data set for encoding into a erasure code group in an alternative blob in the first data center. Further, upon receipt of the global reclamation message from the second data center, indicating the first blob is free in the map in the first data center. In one embodiment, selecting the first blob is based on the map indicating free space in the first data center.

Abstract: A method for memory page erasure-correcting property generation in a storage array includes dividing data into multiple stripes for storage in a storage array including multiple storage devices with a topology of a hypercube of a dimension t?3. The storage devices in same hypercubes of dimension t?1 including the hypercube of dimension t have even parity. An intersection of two non-parallel planes in the hypercube topology is a line, and each point along a line is a storage device in the storage array. Erasure-correcting properties are generated for the data using three nested codes, wherein a first nested code has even parity over planes of class 0, 1 and 2, a second nested code has a first global parity, and a third nested code has a second global parity and a third global parity.

Abstract: A disc cassette includes a curved portion configured to hold multiple discs. A platform portion abuts the curved portion. A movable bale is configured to maintain discs securely in the disc cassette except when rotated off the discs.

Abstract: A disc cassette includes a curved portion configured to hold multiple discs. A platform portion abuts the curved portion. A movable bale is configured to maintain discs securely in the disc cassette except when rotated off the discs.

Abstract: A method for memory page erasure reconstruction in a storage array includes dividing data into multiple stripes for storage in a storage array including multiple storage devices with a topology of a hypercube of a dimension t?3. The storage devices in same hypercubes of dimension t?1 including the hypercube of dimension t have even parity. An intersection of two non-parallel planes in the hypercube topology is a line, and each point along a line is a storage device in the storage array. A reconstructor processor reconstructs erased data for erased memory pages from non-erased data in the storage array by using parities in at least three dimensions based on the hypercube topology of the storage devices.

Abstract: An apparatus includes a first jaw device, a second jaw device, and a disc sensor configured to sense presence of a storage disc between the first jaw device and the second jaw device. The first jaw device and the second jaw device form a gripper device configured to clamp a particular portion of a storage disc including an arc segment along an outer edge of adjacent surfaces of the storage disc.

Abstract: One embodiment provides a method for storing data in a data storage system. The method comprises copying a data set into a buffer in a data storage center in response to receiving a write command for the data set; updating a content map; and sending to a second data storage center a parity write command for the data set. The method continues with copying the data set into a buffer in the second data storage center; updating a second content map; and sending to the first data storage center an acknowledgement indicating the parity write command is complete. Then in response to receiving the acknowledgement, updating the first content map; moving the data set to a storage unit in first data storage center; and acknowledging the data set is protected. Finally, releasing the data set from the first buffer; and updating the first map content.

Abstract: A method and apparatus is provided to enable loading and/or unloading of a storage drive. The body has a first end, a second end, and a path extending from the first end to the second end. The body is configured to receive the computer readable storage device and maintain the computer readable storage device in a first position. The body is configured to passively change orientation from a first orientation to a second orientation responsive to contact from the computer readable storage device. The first orientation maintains the first position of the computer readable storage drive and the second orientation facilitates traversal of the computer readable storage device along the path.

Abstract: A method and apparatus is provided to enable loading and/or unloading of a storage drive. The body has a first end, a second end, and a path extending from the first end to the second end. The body is configured to receive the computer readable storage device and maintain the computer readable storage device in a first position. The body is configured to passively change orientation from a first orientation to a second orientation responsive to contact from the computer readable storage device. The first orientation maintains the first position of the computer readable storage drive and the second orientation facilitates traversal of the computer readable storage device along the path.

Abstract: A method for memory page erasure reconstruction in a storage array includes dividing data into multiple stripes for storage in a storage array including multiple storage devices with a topology of a hypercube of a dimension t?3. The storage devices in same hypercubes of dimension t?1 including the hypercube of dimension t have even parity. An intersection of two non-parallel planes in the hypercube topology is a line, and each point along a line is a storage device in the storage array. A reconstructor processor reconstructs erased data for erased memory pages from non-erased data in the storage array by using parities in at least three dimensions based on the hypercube topology of the storage devices.

Abstract: A method includes distributively encoding data stored in a storage system using an erasure-correcting code. The encoded data is distributed into multiple w storage device arrays in the storage system. Each storage device array includes n storage devices. Each storage device is divided into m sectors or pages. The n storage devices are grouped into l groups of t storage devices each. Data erasures in the w storage device arrays are corrected by recovering erased data using the erasure-correcting code of un-erased data based on each row and column in each m×n array being protected by the erasure-correcting code for the data. Each group of t storage devices contains extra second responder parities to correct extra data erasures in addition to data erasures corrected by first responder vertical parities in each m×t subarray, and w, n, m, l and t are positive integers.

Abstract: A computer-implemented method is provided for increasing the failure tolerance of an array of storage elements in a storage system. The computer-implemented method includes configuring an array to include a plurality of storage elements in n>1 sets of storage elements. The computer-implemented method also includes configuring an erasure-correcting code such that at least one column of the storage elements of the array stores row parity information, and at least one row of the storage elements of the array stores column parity information. Still yet, the computer-implemented method includes, subsequent to a failure of one of the storage elements storing data, selecting a recipient storage element from the array, and rebuilding at least a portion of the data onto the recipient storage element by performing a parity exchange operation that retains a failure tolerance of the set of storage elements containing the failed storage element.

Abstract: A controller including an object aggregator process that combines multiple data objects into a data segment, and transfers the data segment with reduced location metadata to storage media of at least one of multiple storage units. An erasure coder process generates code to encode the data segment into an erasure code that protects against concurrent data loss in the multiple storage units based on data reconstruction using a first responder, a second responder and a last responder.

Abstract: A disc cassette includes a curved portion configured to hold multiple discs. A platform portion abuts the curved portion. A movable bale is configured to maintain discs securely in the disc cassette except when rotated off the discs.

Abstract: A method for distributed coding in a storage array is presented. The method includes dividing data into multiple stripes for storage in a storage array including storage devices with a topology of a hypercube of a dimension t?3. The storage devices in same hypercubes of dimension t?1 including the hypercube of a dimension t have even parity. Global parities are added to the hypercube such that a minimum distance of a code is enhanced.

Abstract: A method for hierarchical correction coding includes converting data for a storage system into w storage device arrays, each storage device array including n storage devices, and each storage device divided into m sectors or pages. The n storage devices are grouped into l groups of t storage devices each. Erasures in the w storage device arrays are corrected based on protecting each row and column in each m×n array by an erasure-correcting code. Each group of t storage devices contains extra parities to correct extra erasures in addition to erasures corrected by vertical parities in each m×t subarray, and w, n, m, l and t are positive integers.

Abstract: A data storage structure, comprising: a plurality of storage units, each comprising: a storage media; and a library executive configured to manage the storage media. The structure further comprises a buffer connected to a controller, the controller comprising: a host interface configured to receive the instruction from the host machine; an object aggregator configured to combine the plurality of data objects into a data segment; a persistent write buffer configured to store the data segment; a persistent map configured to identify a location of each of the plurality of objects in the data segment; an erasure coder configured to encode the data segment into an erasure code; a destager configured to transfer the data segment from the persistent write buffer to the storage media in a given storage unit; and a library controller configured to communicate with the library executive in the given storage unit.

Abstract: Embodiments relate a universal serial bus (USB) filter hub. An aspect includes receiving, by the USB filter hub that is in communication with a host computer system, a connection from a USB device at a USB port of the USB filter hub. Another aspect includes determining, by the USB filter hub, a type of the USB device. Another aspect includes determining whether the type of the USB device is valid. Yet another aspect includes, based on determining that the type of the USB device is valid, filtering commands that are communicated between the USB device and the host computer system via the USB filter hub based on a predetermined command set corresponding to the determined type of the USB device.