Abstract: A method includes receiving, by a storage unit of a dispersed storage network (DSN) an access request for an encoded data a slice of a set of encoded data slices from a computing device of the DSN. The method further includes queueing, by the storage unit, the access request for the encoded data slice. The method further includes, prior to executing the access request, determining, by the storage unit, whether a session associated with the access request is still active and whether execution the access request for encoded data slice is still needed. When the session is still active and the execution of the access request for the encoded data slice is still needed, the method further includes executing, by the storage unit, the access request for the encoded data slice.

Abstract: A method begins by a first computing device of a plurality of computing devices accessing a rebuild hierarchical index structure to identify a data object having encoded data slices requiring rebuilding, where the structure includes a plurality of nodes that organizes a plurality of data objects based on a level of need of rebuilding. The method continues with the first computing device utilizing a rebuilding function to rebuild one or more of the identified encoded data slices to be rebuilt to produce one or more rebuilt encoded data slices and sending a write request to memory of a dispersed storage network to store the one or more rebuilt encoded data slices. The method continues with the first or another computing device updating the level of need of rebuilding of the identified data object and updating the rebuild hierarchical index structure based on the updated level of need of rebuilding.

Abstract: A method includes a processing module of a storage unit of a dispersed storage network (DSN) monitoring input/output (IO) rates of a plurality of disk drives, where access requests for encoded data slices occur at varying rates. The method continues with the processing module determining that the IO rate of a disk drive is exceeding a desired maximum IO rate and identifying a pending access request for an encoded data slice stored in the disk drive. The method continues with the processing module evaluating disk drive processing rates of other storage units that are storing other encoded data slices of a set of encoded data slices that includes the encoded data slice to determine whether the encoded data slice is needed to satisfy the pending access request. When the encoded data slice is needed, the method continues with the processing module migrating the encoded data slice to another disk drive.

Abstract: A method includes receiving, by a storage unit of a dispersed storage network (DSN) an access request for an encoded data a slice of a set of encoded data slices from a computing device of the DSN. The method further includes queueing, by the storage unit, the access request for the encoded data slice. The method further includes, prior to executing the access request, determining, by the storage unit, whether a session associated with the access request is still active and whether execution the access request for encoded data slice is still needed. When the session is still active and the execution of the access request for the encoded data slice is still needed, the method further includes executing, by the storage unit, the access request for the encoded data slice.

Abstract: A method includes a dispersed storage (DS) processing module receiving a request. The method continues by identifying a session associated with the request. The method continues by queueing one or more tasks associated with the request. The method continues by determining whether the session is still active. When the session is not active, the method continues by cancelling the one or more tasks associated with the session prior to execution. When the session is still active, the method continues by executing the first task of the one or more tasks when a task resource is available.

Abstract: A method includes a set of execution units of a dispersed storage network (DSN) receiving sets of sub-task requests from a computing device and storing the sets of sub-task requests, where each execution unit stores a request of each of the sets of sub-task requests to produce a corresponding plurality of sub-task requests. The method continues with each execution unit generating sub-task estimation data and adjusting timing, sequencing, or processing of the corresponding plurality of sub-task requests based on the estimation data to produce a plurality of partial results, where, due to one or more difference factors from a list of difference factors, the execution units process pluralities of sub-task requests at difference paces, where the list of difference factors includes differences in amounts of data to be processed per sub-task request, processing capabilities, memory storage capabilities, and networking capabilities.

Abstract: A method begins by a first computing device of a plurality of computing devices accessing a rebuild hierarchical index structure to identify a data object having encoded data slices requiring rebuilding, where the structure includes a plurality of nodes that organizes a plurality of data objects based on a level of need of rebuilding. The method continues with the first computing device utilizing a rebuilding function to rebuild one or more of the identified encoded data slices to be rebuilt to produce one or more rebuilt encoded data slices and sending a write request to memory of a dispersed storage network to store the one or more rebuilt encoded data slices. The method continues with the first or another computing device updating the level of need of rebuilding of the identified data object and updating the rebuild hierarchical index structure based on the updated level of need of rebuilding.

Abstract: A method includes a set of execution units of a dispersed storage network (DSN) receiving sets of sub-task requests from a computing device and storing the sets of sub-task requests, where each execution unit stores a request of each of the sets of sub-task requests to produce a corresponding plurality of sub-task requests. The method continues with each execution unit generating sub-task estimation data and adjusting timing, sequencing, or processing of the corresponding plurality of sub-task requests based on the estimation data to produce a plurality of partial results, where, due to one or more difference factors from a list of difference factors, the execution units process pluralities of sub-task requests at difference paces, where the list of difference factors includes differences in amounts of data to be processed per sub-task request, processing capabilities, memory storage capabilities, and networking capabilities.

Abstract: A method includes a dispersed storage (DS) processing module receiving a slice access request that includes a slice name. The method continues by obtaining one or more revision numbers for the slice access request. The method continues for each combination of revision number and the slice name, by performing a deterministic function on the combination to produce a slice location table index value. The method continues by accessing a slice location table utilizing the slice location table index value to obtain a slice location. The method continues by accessing a slice utilizing the slice location. The method continues by generating a slice access response based on the accessing of the slice and sending the slice access response to a requesting entity.

Abstract: A method includes a dispersed storage (DS) processing module receiving a request. The method continues by identifying a session associated with the request. The method continues by queueing one or more tasks associated with the request. The method continues by determining whether the session is still active. When the session is not active, the method continues by cancelling the one or more tasks associated with the session prior to execution. When the session is still active, the method continues by executing the first task of the one or more tasks when a task resource is available.

Abstract: A method includes a processing module of a storage unit of a dispersed storage network (DSN) monitoring input/output (IO) rates of a plurality of disk drives, where access requests for encoded data slices occur at varying rates. The method continues with the processing module determining that the IO rate of a disk drive is exceeding a desired maximum IO rate and identifying a pending access request for an encoded data slice stored in the disk drive. The method continues with the processing module evaluating disk drive processing rates of other storage units that are storing other encoded data slices of a set of encoded data slices that includes the encoded data slice to determine whether the encoded data slice is needed to satisfy the pending access request. When the encoded data slice is needed, the method continues with the processing module migrating the encoded data slice to another disk drive.