Abstract: method and apparatus for synchronizing replicated data in a storage network. In an embodiment, a method begins by a processing module of a computing device identifying a first storage set and a second storage set for replicated storage of a data object. The processing module initiates storage of the data object in both the first and second storage sets, and further maintains a synchronization status for the data object. The processing module determines, based at least in part on the synchronization status, to resynchronize the first storage set and the second storage set. In response to determining to resynchronize the first storage set and the second storage set, the processing module identifies a latest available revision of the data object, determines that the second storage set requires the latest available revision of the data object to maintain synchronization, and facilitates storage of the identified latest available revision of the data object in the second storage set.

Abstract: A method for use in a distributed storage network including a distributed storage network (DSN) memory, which in turn includes multiple storage units, includes determining storage parameters associated with error-encoded data slices generated from data to be stored in the DSN memory. The storage parameters include information indicating a read-threshold number of error-encoded data slices required to recover the data. The method further includes distributedly storing the error-encoded data slices among the plurality of storage units so that the number of the error-encoded data slices stored in any particular storage unit is chosen so that in the event of a failure of any individual storage unit, at least a read-threshold number of error-encoded data slices are still accessible from the remaining storage units.

Abstract: A method for execution by at least one processor of a database system includes indexing a first column via a probabilistic indexing scheme. An IO pipeline that includes a probabilistic index-based IO construct for access of the first column is determined based on a query including a query predicate indicating the first column. The probabilistic index-based IO construct is applied in conjunction with execution of the query via the IO pipeline by applying an index element of the probabilistic index-based IO construct to identify a first subset of rows based on index data of the probabilistic indexing scheme for the first column. A filter element of the probabilistic index-based IO construct is applied to identify ones of a first subset of the plurality of column values corresponding to the first subset of rows that compare favorably to the query predicate.

Abstract: A computing device includes processing circuitry configured to determine whether to modify the dispersed error encoding parameters of a set of encoded data slices (EDSs) stored in a distributed storage network to produce a set of modified EDSs, wherein a data object is segmented into a plurality of data segments and in response to a determination to modify the dispersed error encoding parameters of the set of EDSs, identify a plurality of storage units to store the modified EDSs and determine modified dispersed error encoding parameters for the modified EDSs. The computing device is further configured to assign each storage unit of the plurality of storage units to execute one or more storage modification tasks associated with producing the modified EDSs; and transmit one or more EDS of the set of EDSs to each storage unit of the plurality of storage units for modification and storage.

Abstract: A computing device including a processing module configured to receive a read request for a read threshold number of encoded data slices of the set of encoded data slices, determine whether a read threshold number of encoded data slices of the set of encoded data slices is available in a set of storage units associated with a first storage site and when a read threshold number of encoded data slices of the set of encoded data slices is not available in the set of storage units associated with a first storage site, transmit a read request for a read threshold number of encoded data slices to the set of storage units associated with a second storage site.

Abstract: A processing system of a storage network operates by: sending, to at least one storage unit of the storage network, at least one read request corresponding to at least a read threshold number of a set of encoded data slices to be retrieved, wherein the set of encoded data slices correspond to a data segment, wherein the data segment is coded in accordance with dispersed error coding parameters that include a write threshold number and the read threshold number, wherein the write threshold number is a number of encoded data slices in the set of encoded data slices and wherein the read threshold number is a number of the set of slices that is required to decode the data segment; receiving, via the at least one processing circuit and from the at least one storage unit, a first subset of encoded data slices of the set of encoded data slices, wherein the first subset of encoded data slices is missing at least one missing encoded data slice that was not received from the at least one storage unit in response to the

Abstract: A method for execution by at least one processor of a database system includes storing a plurality of column values for a first column of a plurality of rows. Each of a set of missing data-based conditions for the first column are indexed via an indexing scheme. A subset of the set of missing data-based conditions that satisfy a query predicate of a query are identified. An IO pipeline for access of the first column based on the query predicate and further based on the subset of the set of missing data-based conditions is generated. The IO pipeline is applied in conjunction with execution of the query by applying at least one index element to identify a proper subset of the plurality of rows based on index data of the indexing scheme, and by generating a query resultant based on the proper subset.

Abstract: A method includes determining a storage modification process for a set of encoded data slices based on a change to the storage parameters associated with storage of data objects in a storage network, where a data segment of the data objects is dispersed storage error encoded into the set of encoded data slices in accordance with dispersed storage error encoding parameters, and where the set of encoded data slices is stored in the storage network. The method also includes executing the storage modification process such that the set of encoded data slices are stored in the storage network in accordance with the changed storage parameters.

Abstract: A method begins by a processing module receiving a request to store a data object in distributed storage (DS) units. The processing module generates and transmits a proposal message that includes a preferred source name, and a proposal attempt identifier to a plurality of DS units. The processing module then receives a proposal message acceptance response from at least one of the plurality of DS units and when the proposal message response indicates that no other proposal messages have been received by at least one of the plurality of DS units, retains the preferred source name included within the proposal message as a persistent value for the source name.

Abstract: A method for use in a distributed storage network includes determining storage parameters associated with error-encoded data slices generated from data to be stored in the distributed storage network. The storage parameters include information indicating a read threshold number of error-encoded data slices required to recover the data. Storage requirements of a storage unit included in the distributed storage network are also determined. The storage unit includes multiple memory devices configured to store one or more error-encoded data slices of the read threshold number of error-encoded data slices. A number of the one or more error-encoded data slices are stored in the storage unit based on the storage requirements of the storage unit and the storage parameters.

Abstract: A method for execution by a dispersed storage network (DSN). The method begins by obtaining a data object for synchronized storage within a plurality of storage vaults, identifying a plurality of storage vaults, encoding the data object for each storage vault, initiating storage of data slices for each storage vault and interpreting received data slice information from at least some of the storage vaults to determine a number of storage vaults that have successfully stored the corresponding plurality of sets of encoded data slices and when the vault threshold number of storage vaults have not successfully stored the corresponding plurality of sets of encoded data slices within a synchronization timeframe, initiating a rollback process to abandon storage of the data object in the plurality of storage vaults and a store data response to indicate unsuccessful synchronized storage of the data object in the plurality of storage vaults.

Abstract: A method includes dispersed storage error encoding a data object to produce a set of encoded data slices. The method further includes obtaining routing path performance information for a plurality of routing paths from the computing device to a set of storage units. The method further includes selecting a first routing path for sending a first subset of the set of encoded data slices, where the first routing path has a performance level greater than a first performance threshold. The method further includes selecting a second routing path for sending a second subset of the set of encoded data slices, where the second routing path has a performance level less than or equal to the first performance threshold. The method further includes sending the first and second subsets of encoded data slices to the set of storage units via the first and second routing paths for storage therein.

Abstract: A method for execution by a computing device of a storage network includes obtaining storage performance information for a set of storage units of the storage network, where data segments are dispersed storage error encoded into pluralities of sets of encoded data slices in accordance with error encoding parameters that include a pillar width number and a decode threshold number, which is a number of encoded data slices the set of encode data slices is required to reconstruct a data segment of data segments. The method further includes determining, based on the storage performance information and the error encoding parameters, a performance threshold number for a write request to store a set of encoded data slices of the pluralities of sets of encoded data slices in the set of storage units, where the performance threshold number is greater than the decode threshold number and less than the pillar width number.

Abstract: A storage network receives data and a corresponding task, selects a storage units for the task, determines whether the data slice is locally available and when the data slice is not locally available, determines whether a redundant data slice is available from another storage unit. When the redundant data slice is not available from another storage unit, the storage network facilitates rebuilding the data slice to produce a rebuilt data slice by retrieving a decode threshold number of data slices corresponding to the data slice, decoding the decode threshold number of data slices to reproduce a data segment and re-encoding the data segment to produce a pillar width number of data slices that includes the rebuilt data slice.

Abstract: Event records from multiple computing devices are received at a managing unit. Individual event records include an event identifier field including an event identifier identifying a first event associated with a particular computing device, a parent event identifier field identifying a parent event that initialized the first event, and an entity identifier field including an entity identifier identifying the particular computing device. The managing unit generates log records associated with event identifiers included in the event records. The log records include state fields indicating a state of a particular event associated with a particular event identifier. Based on a correlation of the event and log records, the managing unit determines at least two computing devices associated with events resulting in an error state, and identifies parent events that initialized the events with errors. The managing unit generates a report linking the parent events to the events having an error state.

Abstract: A method for execution by a storage network includes receiving a request pertaining to a data object. Metadata associated with the data object is determined and used to identify data segments associated with the data object and a set of storage units associated with the data segments. Based on a set of query requests, a response is received from a storage unit from the set of storage units. When the response indicates a storage environment that is unfavorable as compared to predetermined performance metrics, the storage network facilitates migration of encoded data slices associated with the storage unit to another storage unit.

Abstract: Apparatus for tiered storage of data in a storage network. In an example of operation, a computing device receives a data object for storage and forwards the data object for storage in a first plurality of memory devices of a first memory type. The computing device determines a system level storage efficiency for the data object based, at least in part, on a data attribute associated with the data object. The computing device further selects, based at least in part on the system level storage efficiency preference, a second plurality of memory devices comprised of a second memory type. The computing device determines error encoding parameters based on the second plurality of memory devices, retrieves the data object from the first plurality of memory devices, and encodes the data object with the error encoding parameters to generate a plurality of encoded data slices for storage in the second plurality of memory devices.

Abstract: A method for execution by one or more processing modules of one or more computing devices begins by encoding data using a dispersed storage error encoding function to produce a plurality of sets of encoded data slices arranged into a plurality of chunksets of encoded data slices. The method continues by selecting a set of storage units for storing the plurality of chunksets and assigning a distributed computing task to each storage unit of the set of storage units. The method then continues by generating a unique key set for each storage unit of the storage units, encrypting each chunkset of encoded data slices with a corresponding one of the unique key sets to produce a plurality of encrypted chunksets and sending an encrypted chunkset of the plurality of encrypted chunksets and an indication of a corresponding distributed computing task to each storage unit of the set of storage units for storage of the encrypted chunksets and execution of the distributed computing task.

Abstract: A method includes determining a change to storage parameters associated with storage of data objects in a storage network, where a data segment of the data objects is dispersed storage error encoded into a set of encoded data slices based on dispersed storage error encoding parameters, and where the set of encoded data slices is stored in the set of storage units. The method also includes determining a storage modification process for the set of encoded data slices based on the change to the storage parameters. The method also includes executing the storage modification process such that the set of encoded data slices are stored in the storage network in accordance with the changed storage parameters.

Abstract: A processing system of a storage network operates by: sending, to at least one storage unit of the storage network, at least one read request corresponding to at least a read threshold number of a set of encoded data slices to be retrieved, wherein the set of encoded data slices correspond to a data segment, wherein the data segment is coded in accordance with dispersed error coding parameters that include a write threshold number and the read threshold number, wherein the write threshold number is a number of encoded data slices in the set of encoded data slices and wherein the read threshold number is a number of the set of slices that is required to decode the data segment; receiving, via the at least one processing circuit and from the at least one storage unit, a first subset of encoded data slices of the set of encoded data slices, wherein the first subset of encoded data slices is missing at least one missing encoded data slice that was not received from the at least one storage unit in response to the