摘要:
The present invention relates to a method for reducing data loss comprising a first computing step for computing an intermediate result for each redundancy information entity of a redundancy set by processing respectively associated data information entities of a given data set on at least two main diagonals of a parity check matrix representing an error correction coding scheme. The method further comprises a second computing step for computing the information content of the respective redundancy information entity dependent on the respective intermediate result.
摘要:
One embodiment disclosed is method for protecting data stored on at least one storage unit against uncorrectable media errors. The method includes associating a given redundancy set of at least one redundancy information sector (R) with a given data set of at least two data information sectors (D). The information content of the redundancy set is computed dependent on the information content of the data set. A storing operation stores the information content of the redundancy set consecutively with the information content of the data set forming a segment such that the redundancy set is placed logically in between a first part and a second part of the data set, and accessing at least one data information sector (D) in the data set by reading and/or writing the information content of the at least one data information sector (D) and at least one redundancy information sector (R) in the redundancy set with a single request.
摘要:
The present invention is related to a method for allocating pending requests for data packet transmission at a number of inputs to a number of outputs of a switching system in successive time slots, wherein according to a matching method the allocation of the pending requests is optimized, wherein the matching method includes a number of steps for incrementally allocating the requests, wherein as a result of each step a matching information is provided, wherein in each time slot a request information is provided, the request information indicating the data packets at the inputs requesting transmission to respective outputs, the matching method comprising the steps of providing a first request information in a first time slot, performing a first step in the first time slot depending on the first request information to obtain a first matching information; providing a last request information in a last time slot successive the first time slot; performing a last step in the last time slot depending on the last request information and depending on the first matching information to obtain a final matching information; and assigning the pending data packets at the number of inputs to the number of outputs in dependence on the final matching information.
摘要:
A flow control method is practiced in a first node in a computer network having one or more upstream nodes, each of which can provide data cells to the first node over a connection. Cells are transmitted over a connection during an established transmission period for that connection and at a data rate not exceeding a peak data rate. To determine whether a buffer is sufficient during a given time period starting at the current time, the potential buffer requirements during that time period are established as a function of the current buffer occupancy and the maximum number of cells which may be received during the given time period. If the potential buffer requirements exceed a predetermined buffer threshold, one or more stop signals is sent to upstream sources to limit the number of cells to be provided to the first node.
摘要:
In a communication switch with input and output queueing, which handles different priority classes of traffic (e.g. video and audio applications with a high priority, and file transfers and e-mail as low priority traffic), the invention provides a timed shut-off mechanism at each input queue. This mechanism is activated when an input queue attempting to transmit low-priority traffic gets a backpressure signal. The mechanism interrupts further attempts to transmit low priority traffic for a predetermined period of T switching cell cycles. Hence, during the shut-off periods, the output queue is only used by the high priority traffic. Therefore, the performance of the high priority traffic is preserved.
摘要:
A mechanism is provided for controlling a solid state storage device in which the solid state storage comprises erasable blocks each comprising a plurality of data write locations. Input data is stored in successive groups of data write locations, each group comprising write locations in a set of erasable blocks in each of a plurality of logical subdivisions of the solid state storage. The input data is error correction encoded such that each group contains an error correction code for the input data in that group. Metadata, indicating the location of input data in the solid state storage, is maintained in memory. An indication of validity of data stored in each data write location is also maintained. Prior to erasing a block, valid input data is recovered from the group containing write locations in that block. The recovered data is then re-stored as new input data.
摘要:
A method and apparatus for managing write operations in memory. The method includes a memory including units, each of the units including subunits. Data updates are written “out-of-place”, in that new data does not overwrite the memory locations (subunits) where the data is currently stored. The at least one subunit containing the outdated data is marked as invalid. As a result, a subunit can contain up to date data in a valid subunit next to invalid subunits. For reclaiming units for erasure, it is searched amongst the units to identify a unit or units that match a predetermined criterion. The data of valid subunits of such identified unit is rewritten to another unit or units.
摘要:
A method and apparatus for decoding a codeword received from a flash memory. The flash memory comprises multi-level flash memory cells, wherein each multi-level flash memory cell stores one symbol of the codeword. An ECC decoder is arranged for decoding the codeword into a decoded codeword and correcting a maximum number of errors. The method determines the number of errors in the codeword. If the number of errors is more than the maximum number of errors that the ECC decoder can correct, the method generates modified codewords, calculates a corrective effect of a modified codeword, and determines a decoded codeword based on the corrective effect.
摘要:
A system, method apparatus, and computer readable medium for managing renewal of a dynamic set of data items. Each data item has an associated renewal deadline, in a data item management system. A renewal schedule allocates to each data item a renewal interval for renewal of the data item. On addition of a new data item, if a potential renewal interval having a duration required for renewal of the data item, and having an ending at the renewal deadline for that item does not overlap a time period in the schedule during which the system is busy, the renewal schedule is automatically updated by allocating the potential renewal interval to the new data item. If the potential renewal interval does overlap a busy period, the renewal schedule is automatically updated by selecting an earlier renewal interval for at least one data item in the set.
摘要:
A method for garbage collection in a solid state drive (SSD) includes determining whether the SSD is idle by a garbage collection module of the SSD; based on determining that the SSD is idle, determining a victim block from a plurality of memory blocks of the SSD; determining a number of valid pages in the victim block; comparing the determined number of valid pages in the victim block to a valid page threshold; and based on the number of valid pages in the victim block being less than the valid page threshold, issuing a garbage collection request for the victim block.