Making consistent reads more efficient in IDA+copy system

A computing device comprising:

• an interface configured to interface and communicate with a dispersed or distributed storage network (DSN);
• memory that stores operational instructions;
• and
• processing circuitry operably coupled to the interface and to the memory, wherein the processing circuitry is configured to execute the operational instructions to:
• receive, via the interface and via the DSN, a data access request for a data object from another computing device, wherein the data object is segmented into a plurality of data segments, wherein a data segment of the plurality of data segments is dispersed error encoded in accordance with dispersed error encoding parameters to produce a set of encoded data slices (EDSs) that are distributedly stored among a first plurality of storage units (SUs) within the DSN, wherein a decode threshold number of EDSs are needed to recover the data segment, wherein a trimmed copy of the set of EDSs that includes fewer than all EDSs of the set of EDSs and includes at least the decode threshold number of EDSs are distributedly stored among a second plurality of SUs within the DSN, wherein another trimmed copy of the set of EDSs are distributedly stored among a third plurality of SUs within the DSN, wherein the data segment of the plurality of data segments is dispersed error encoded in accordance with other dispersed error encoding parameters to produce another set of EDSs, wherein another decode threshold number of the another set of EDSs are needed to recover the data segment;
• issue, via the interface and via the DSN, at least one of a first read request or a first check request to the first plurality of SUs to determine a first revision number that corresponds to the set of EDSs that are distributedly stored among the first plurality of SUs;
• issue, via the interface and via the DSN, at least one of a second read request or a second check request to the second plurality of SUs to determine a second revision number that corresponds to the trimmed copy of the set of EDSs that are distributedly stored among the second plurality of SUs;
• and
• based on a favorable comparison of the first revision number of the set of EDSs and the second revision number of the trimmed copy of the set of EDSs, issue, via the interface and via the DSN, the data access request for the data object based on the at least the decode threshold number of EDSs to at least one of the set of EDSs that are distributedly stored among the first plurality of SUs or the trimmed copy of the set of EDSs that are distributedly stored among the second plurality of SUs.

A method for execution by a computing device, the method comprising:

• receiving, via an interface of the computing device that is configured to interface and communicate with a dispersed or distributed storage network (DSN) and via the DSN, a data access request for a data object from another computing device, wherein the data object is segmented into a plurality of data segments, wherein a data segment of the plurality of data segments is dispersed error encoded in accordance with dispersed error encoding parameters to produce a set of encoded data slices (EDSs) that are distributedly stored among a first plurality of storage units (SUs) within the DSN, wherein a decode threshold number of EDSs are needed to recover the data segment, wherein a trimmed copy of the set of EDSs that includes fewer than all EDSs of the set of EDSs and includes at least the decode threshold number of EDSs are distributedly stored among a second plurality of SUs within the DSN;
• and
• based on a favorable comparison of a first revision number of the set of EDSs and a second revision number of the trimmed copy of the set of EDSs, issuing, via the interface and via the DSN, the data access request for the data object based on the at least the decode threshold number of EDSs to at least one of the set of EDSs that are distributedly stored among the first plurality of SUs or the trimmed copy of the set of EDSs that are distributedly stored among the second plurality of SUs.