A system includes a plurality of storage units each including a network port operably coupled to the network, where one or more storage vaults is associated with the plurality of storage units and each storage vault of the one or more storage vaults represents a software-constructed grouping of storage units of the plurality of storage units, where the software-constructed grouping of storage units stores encoded data slices, where a data segment is encoded using an information dispersal algorithm to produce the encoded data slices, and where a storage unit: receives, via the network port, a request regarding the data segment stored in the software-constructed grouping of storage units, obtains, from a data structure pertaining to the software-constructed grouping of storage units, information regarding the request, determines whether the request is valid based on the information regarding the request, and when the request is valid, the storage unit executes the request.

A method begins by a first computing device determining a routing plan to route a set of encoded data slices from the first computing device to a second computing device via a plurality of network paths of a communications network. The method continues with the second computing device receiving encoded data slices via one or more network paths. When the second computing device receives a decode threshold number of encoded data slices, the method continues with the second computing device sending a message to the communications network indicating receipt of the decode threshold number of encoded data slices. The method continues with a relay unit determining whether the relay unit is in possession of a not-yet delivered encoded data slice. When the relay unit is in possession of the not-yet delivered encoded data slice, the method continues with the relay unit ceasing forwarding of the not-yet delivered encoded data slice.

A storage unit operates by: receiving a write slice request, wherein the write slice request includes a plurality of encoded data slices and wherein the write slice request corresponds to a range; determining whether a write lock conflict exists based on the range; issuing an unfavorable write slice response when the write lock conflict is determined to exist; and when the write lock conflict is determined to not exist: initiating local storage of the plurality of encoded data slices; and issuing a favorable write slice response.

A method begins by a processing module of a dispersed storage network (DSN) obtaining utilization information regarding a plurality of storage units of the DSN, where first and second sets of storage units support a first logical storage vault. The method continues with the processing module detecting a utilization imbalance between a first storage unit of the first set of storage units and a second storage unit of the second set of storage units based on the utilization information, where the first and second storage units are not a common storage unit. The method continues with the processing module executing a data storage function regarding the first logical storage vault based on the utilization imbalance.

Techniques described and suggested herein include systems and methods for optimizing performance characteristics by differentiating data storage device types for data archives stored on data storage systems using redundancy coding techniques. For example, redundancy coded shards, which may include identity shards that contain unencoded original data of archives, may be stored on different types of data storage devices to optimize for various retrieval use cases and implemented environments. Implementing systems may monitor various performance characteristics so as to adaptively account for changes to some or all of the monitored parameters.

A method for execution by one or more processing modules of a storage network begins by receiving an access request for a set of encoded data slices, where the data object is segmented into a plurality of data segments, a data segment of which is dispersed error encoded in accordance with dispersed error encoding parameters to produce the set of encoded data slices. The method continues by determining whether a revision for one or more encoded data slices in a first storage module is a most recent revision level for the one or more encoded data slices and when the one or more encoded data slices is a most recent revision level, determining whether the revision level for the one or more encoded data slices in a second storage module is the most recent revision level. When the one or more encoded data slices in the second storage module is not the most recent revision level the method continues by facilitating a read request to the first storage module for the one or more encoded data slices and synchronizing the one or more encoded data slices in the second storage module with the one or more encoded data slices in the first storage module.

The method begins with a processing module determining whether to reconstruct data corresponding to a plurality of data slices when the plurality of data slices is to be transferred from a first type of memory device to a second type of memory device. The method continues with the processing module retrieving the plurality of data slices from a first set of memory devices that are of the first type of memory, reconstructing at least a portion of the data from the plurality of data slice in accordance with a first error coding dispersal function to produce reconstructed data, encoding the reconstructed data in accordance with a second error coding dispersal function to produce a second plurality of data slices, and storing the second plurality of data slices in a second set of memory devices that are of the second type of memory when the data is to be reconstructed.

Data is stored as a first collection of memory blocks distributed across a first set of memory devices. It is determined that a first memory device in the first set is in a degraded state. Data is recovered corresponding to a first memory block in the first collection of memory blocks that is stored in the first memory device, which is configured to include a first number of memory blocks. The recovered data is stored in a second memory device as a new memory block, which is added to the first collection of memory blocks. The first memory device is removed from the first set and reconfigured with a second number of memory blocks that is less than the first number of memory blocks. Memory blocks in a second collection of memory blocks distributed across a second set of memory devices is stored in the reconfigured first memory device.

A computing device includes interfaces and communicates with a dispersed storage network (DSN) and issues write slice requests to a set of storage units (SUs) to store distributedly a set of encoded data slices (EDSs) associated with a data object. When at least a write threshold number of favorable write slice responses are received, the computing device identifies an EDS without write confirmation and an SU associated therewith. The computing device stores the EDS without write confirmation in a slice cache memory and, based on a determination to reissue a write slice request associated with the EDS without write confirmation, the computing device reissues the write slice request. When a favorable write slice response is received from the SU associated with the EDS without write confirmation, the computing device deletes the EDS of the at least the write threshold number of EDSs without write confirmation from the slice cache memory.

A network storage system operates by: sending, to at least one storage unit of a 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 codable 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 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 from the number of the set of slices that is required to decode the data segment and that was not received from the at least one storage unit in response to the at least one read request; generating at least one rebuilt encoded data slice corresponding to the at least one missing encoded data slice utilizing locally decodable redundancy data, wherein the locally decodable redundancy data includes a plurality of local redundancy slices generated from a second subset of the set of encoded data slices that includes the at least one missing encoded data slice; and recovering the data segment based on the at least one rebuilt encoded data slice and the first subset of encoded data slices.