摘要:
A back-up power source and a back-up storage device are utilized to power a processor and a volatile memory device during a primary power failure. An emergency data-storage algorithm is invoked to create a table of modified data analogous to data residing in a non-volatile memory device associated with a different processor. This table of modified data is written to the back-up storage device.
摘要:
A method to convert a plurality of sectors from a first sector format to a second sector format is disclosed. The method provides (N) contiguous first sectors comprising a first sector format to a sector format conversion device which includes a buffer and a data queue, where those (N) first sectors comprise a first number of bytes, and determines that (M) contiguous second sectors, comprising a second sector format, comprise at least the first number of bytes. The method overlays the (i)th first sector onto part or all of the (j)th second sector, and enqueues the newly-overlain (j)th second sector. The method then transmits the newly-overlain (j)th second sector to a data storage device, and writes that (j)th overlain second sector to an information storage medium.
摘要:
A method to convert a plurality of sectors from a first sector format to a second sector format is disclosed. The method provides (N) contiguous first sectors to a sector format conversion device, where those (N) first sectors include a beginning first sector and a first number of bytes, and determines that (M) contiguous second sectors comprise at least the first number of bytes, where those (M) contiguous sectors include a beginning second sector and an ending second sector. The method overlays the beginning first sector onto the beginning second sector, and overlays the (i)th first sector onto part or all of the (j)th second sector. The method then transmits the newly-formed (j)th second sector to a data storage device, and writes that (j)th second sector to an information storage medium.
摘要:
A method is disclosed to preserve data integrity during loss of power to an information storage and retrieval system. Applicants' method converts a plurality of sectors having a first sector format to a plurality of sectors having a second sector format. If a power failure warning is received during the sector format conversion process, the method prefetches the next second sector, overlays the next first sector onto part of all of that prefetched second sector, and saves the newly-written second sector before loss of utility power. After restoration of utility power to the information storage and retrieval system, Applicants' method writes that newly-written second sector to an information storage medium.
摘要:
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.
摘要:
A method 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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
A method is disclosed to set the signaling rate of a switch domain disposed in an information storage and retrieval system. The method establishes a switch domain target operating speed, and determines if that switch domain target operating speed comprises a first signaling rate. If the switch domain target operating speed comprises a first signaling rate, then the method asserts first Device Control Code bits to each of the plurality of data storage devices, and each of the plurality of data storage devices communicates with the switch using that first signaling rate. If the switch domain target operating speed does not comprise the first signaling rate, then the method asserts second Device Control Code bits to each of the plurality of data storage devices, and each of the plurality of data storage devices communicates with the switch using a second signaling rate.