摘要:
A system and method for scheduling read and write operations among a plurality of solid-state storage devices. A computer system comprises client computers and data storage arrays coupled to one another via a network. A data storage array utilizes solid-state drives and Flash memory cells for data storage. A storage controller within a data storage array comprises an I/O scheduler. The data storage controller is configured to receive requests targeted to the data storage medium, said requests including a first type of operation and a second type of operation. The controller is further configured to schedule requests of the first type for immediate processing by said plurality of storage devices, and queue requests of the second type for later processing by the plurality of storage devices. Operations of the first type may correspond to operations with an expected relatively low latency, and operations of the second type may correspond to operations with an expected relatively high latency.
摘要:
A system and method for maintaining a mapping table in a data storage subsystem. A data storage subsystem supports multiple mapping tables. Records within a mapping table are arranged in multiple levels which may be logically ordered by time. Each level stores pairs of a key value and a pointer value. New records are inserted in a created new (youngest) level. All levels other than the youngest may be read only. In response to detecting a flattening condition, a data storage controller is configured to identify a group of two or more adjacent levels of the plurality of levels for flattening which are logically adjacent in time. A new level is created and one or more records stored within the group are stored in the new level, in response to detecting each of the one or more records stores a unique key among keys stored within the group.
摘要:
A system and method for offset protection data in a RAID array. A computer system comprises client computers and data storage arrays coupled to one another via a network. A data storage array utilizes solid-state drives and Flash memory cells for data storage. A storage controller within a data storage array is configured to store user data in a first page of a first storage device of the plurality of storage devices; generate intra-device protection data corresponding to the user data, and store the intra-device protection data at a first offset within the first page. The controller is further configured to generate inter-device protection data corresponding to the first page, and store the inter-device protection data at a second offset within a second page in a second storage device of the plurality of storage devices, wherein the first offset is different from the second offset.
摘要:
A system and method for effectively scheduling read and write operations among a plurality of solid-state storage devices. A computer system comprises client computers and data storage arrays coupled to one another via a network. A data storage array utilizes solid-state drives and Flash memory cells for data storage. A storage controller within a data storage array comprises an I/O scheduler. The characteristics of corresponding storage devices are used to schedule I/O requests to the storage devices in order to maintain relatively consistent response times at predicted times. Should a device exhibit an unscheduled behavior which may be indicative of the device being in an unknown state, the scheduler may schedule one or more reactive operations on the device configured to cause the device to enter a known state.
摘要:
Disclosed is a method and apparatus for refreshing a copy of a data volume. In one embodiment of the method first and second data portions of a data volume are copied to first and second memory blocks, respectively, of a memory coupled to a computer system. First and second bits of a first map stored in memory are then set, wherein the first and second bits correspond to the first and second memory blocks, respectively. The first data portion of the data volume is modified after the first data portion is copied to the first memory block. A first bit in a second map stored in memory is set after data of the first data portion is modified. An instruction is generated to refresh the data contents of the first and second memory blocks. The first bit of the first map is cleared in response to generation of the refresh instruction.
摘要:
Methods and systems to bridge storage management software are provided. A first storage management application communicates with a host and performs an analysis of a storage environment associated with the host. The first storage management application uses the analysis to determine if a storage resource interface is controlled by a second storage management application, and if so a plugin application is accessed by the first storage management application to permit the second storage management application to perform a storage management operation on behalf of the host. In one embodiment, the analysis is updated by the first storage management application upon receiving results from second storage management application, where the results reflect the processing of the storage management operation by the second storage management application.
摘要:
A system and method for dynamic RAID geometries. A computer system comprises client computers and data storage arrays coupled to one another via a network. A data storage array utilizes solid-state drives and Flash memory cells for data storage. A storage controller within a data storage array is configured to configure a first subset of the storage devices for use in a first RAID layout, the first RAID layout including a first set of redundant data. The controller further configures a second subset of the storage devices for use in a second RAID layout, the second RAID layout including a second set of redundant data. Additionally, when writing a stripe, the controller may select from any of the plurality of storage devices for one or more of the first RAID layout, the second RAID layout, and storage of redundant data by the additional logical device.
摘要:
A system, method, and computer-readable storage medium for mapping block numbers within a region to physical locations within a storage system. Block numbers are mapped within a region according to a fractal-based space-filling curve. If the region is not a 2k by 2k square, then the region is broken up into one or more 2k by 2k squares. Any remaining sub-region is centered within a 2k by 2k square, the 2k by 2k square is numbered using a fractal-based space-filling curve, and then the sub-region is renumbered by assigning numbers based on the order of the original block numbers of the sub-region.
摘要:
A system and method for intra-device data protection in a RAID array. A computer system comprises client computers and data storage arrays coupled to one another via a network. A data storage array utilizes solid-state drives and Flash memory cells for data storage. A storage controller within a data storage array is configured to identify a unit of data stored in the data storage subsystem, wherein said unit of data is stored across at least a first storage device and a second storage device of the plurality of storage devices, each of the first storage device and the second storage device storing intra-device redundancy data corresponding to the unit of data; and change an amount of intra-device redundancy data corresponding to the unit of data on only the first storage device.
摘要:
A system and method for managing multiple fingerprint tables in a deduplicating storage system. A computer system includes a storage medium, a first fingerprint table comprising a first plurality of entries, and a second fingerprint table comprising a second plurality of entries. Each of the first plurality of entries and the second plurality of entries are configured to store fingerprint related data corresponding to data stored in the storage medium. A storage controller is configured to select the first fingerprint table for storage of entries corresponding to data stored in the data storage medium that has been deemed more likely to be successfully deduplicated than other data stored in the data storage medium; and select the second fingerprint table for storage of entries corresponding to data stored in the data storage medium that has been deemed less likely to be successfully deduplicated than other data stored in the storage medium.