Abstract: A method, computer program product, and computing system for storing a plurality of frontend data chunks within a cache system. The plurality of frontend data chunks correspond to a plurality of backend data chunks stored within a data array. A device weight is determined for each of the plurality of backend data chunks. The device weight is indicative of the type of storage device upon which each of the plurality of backend data chunks is stored within the data array. A deletion score is assigned to each of the plurality of frontend data chunks. Each deletion score is based, at least in part, upon the device weight determined for its corresponding backend data chunk.

Abstract: Example embodiments of the present invention relate to a method and a system for improving performance of flash cache memory, such as in a host of a storage environment, for example, by preventing a cache cell from reaching an operation limit. The method includes determining that a number of operations to a first cell of a flash memory has reached a threshold and managing the flash memory according to the determination to prevent a failure of a second cell of the flash memory.

Abstract: A computer-executable method, system, and computer program product for managing a data storage system, wherein the data storage system includes a host-cache and a data storage array, the computer-executable method, system, and computer program product comprising receiving an I/O request, processing the I/O request by locating data related to the I/O request and aligning the I/O request with the data to create an aligned portion of data, and updating the data storage array with the aligned portion of data.

Abstract: Example embodiments of the present invention relate to a method, an apparatus, and a computer program product for sending an I/O over a preferred path. The method includes determining a preferred path to an address range of a virtual storage unit striped across a plurality of disks of a data storage system and sending an I/O for data comprising the address range over the preferred path.

Abstract: A method, computer program product, and computing system for monitoring data requests made by an application being executed on a host to generate a prediction concerning a quantity of data that may be needed by the application in the future. The quantity of data is stored within a backend cache system included within a data array coupled to the host. The quantity of data is provided to the host.

Abstract: A method, computer program product, and computing system for receiving an indication that a hard disk drive within a data array is failing, thus defining a failing hard disk drive. At least a portion of the data included within the failing hard disk drive is copied to a failover portion of a front end cache system included within a host coupled to the data array, thus defining a backup data set.

Abstract: In one aspect, a method includes sending a conditional read request from a host to a storage array requesting data in a data block stored at the storage array. The conditional read request includes a first hash of data in the data block at the host. The method also includes determining a second hash of the data in the data block stored at the storage array, comparing the first hash and the second hash, sending a reply from the storage array to the host with the data in the data block stored at the storage array if the first hash and the second hash differ and sending a reply from the storage array to the host without the data in the data block stored at the storage array if the first hash and the second hash are the same.

Abstract: In one aspect, a method includes determining locations in a file that have changed using read signature commands, reading data around a changed file location for each file location that has changed, generating variable-size portions of the data read and sending the variable-size portions of the data to a backup system.

Abstract: Described are techniques for representing and using RAID group consistency information. RAID group consistency information for a slice of data included on a device may be obtained by mapping the slice to an index. The index is one of a plurality of indices each associated with a structure indicating RAID group inconsistencies for a different portion of slices of data of the device. If the index is not associated with a structure, it may be determined that there is no RAID group inconsistency for the slice. If the index is associated with a structure, a hint bit associated with the slice may be determined wherein the hint bit encodes summary consistency information for a plurality of slices. A determination is made as to whether the hint bit is set, and, if the hint bit is not set, it is determined that there is no RAID group inconsistency for the slice.

Abstract: Embodiments of the invention exploit the fact that not all portions of a logical volume may include data written by a host. Accordingly, an embodiment of the invention includes setting a designated set of bits to 1 in a meta data table when a logical volume is initialized. These bits may be referred to herein as Never Written by Host (NWBH) bits. Separately, or in combination, an embodiment of the invention includes setting a NWBH bit to 0 when data is written to the associated portion of the logical volume. Separately, or in combination, an embodiment of the invention includes reading the NWBH bit upon receiving a read command associated with the associated portion of the logical volume. If the NWBH bit is equal to 1, data is not read from the associated portion of the logical volume; if the NWBH bit is equal to 0, data is read from the associated portion of the logical volume.

Abstract: A method for managing data in a computer system comprises identifying a data-set that has data unit protection that is suspected of having been corrupted, suspending a data unit protection process for the data-set; deferring re-establishing the data unit protection process for the data-set until issuance of a request for an I/O operation for the data unit; and re-establishing the data unit protection process for the data-set in response to the request and before the I/O operation is conducted. The data has a data unit protection invalidity indicator for indicating that the data-set has data unit protection that is suspected of having been corrupted; and the data unit protection process is suspended in the presence of the data-set protection invalidity indicator. Meta-data protection that is suspected of having been corrupted may be used to identify a corrupted data-set.

Abstract: A method for recovering meta-data that has been subjected to corruption is disclosed for a cache memory. Each table entry in the cache memory has an in-cache indicator for indicating whether the data unit associated therewith is stored in a cache-slot in the cache memory. A first review is conducted of the table entries for identifying in-cache table entries (those that are associated with cache-slots in the cache memory), performing a correction attempt to ensure that the meta-data in an in-cache table entry are validated and corrected, if necessary, and ensuring that the in-cache indicator is set for an in-cache table entry. A second review is conducted of the table entries to ensure that the in-cache indicator is not set for any table entry that is not an in-cache table entry or for any in-cache table entry for which the correction attempt was unsuccessful.

Abstract: A method for managing data in a computer system comprises identifying a data-set that has data unit protection that is suspected of having been corrupted, suspending a data unit protection process for the data-set; deferring re-establishing the data unit protection process for the data-set until issuance of a request for an I/O operation for the data unit; and re-establishing the data unit protection process for the data-set in response to the request and before the I/O operation is conducted. The data has a data unit protection invalidity indicator for indicating that the data-set has data unit protection that is suspected of having been corrupted; and the data unit protection process is suspended in the presence of the data-set protection invalidity indicator. Meta-data protection that is suspected of having been corrupted may be used to identify a corrupted data-set.

Abstract: A method for recovering meta-data that has been subjected to corruption is disclosed for a cache memory. Each table entry in the cache memory has an in-cache indicator for indicating whether the data unit associated therewith is stored in a cache-slot in the cache memory. A first review is conducted of the table entries for identifying in-cache table entries (those that are associated with cache-slots in the cache memory), performing a correction attempt to ensure that the meta-data in an in-cache table entry are validated and corrected, if necessary, and ensuring that the in-cache indicator is set for an in-cache table entry. A second review is conducted of the table entries to ensure that the in-cache indicator is not set for any table entry that is not an in-cache table entry or for any in-cache table entry for which the correction attempt was unsuccessful.