COORDINATING CACHE MEMORY UPDATES IN A DISPERSED STORAGE NETWORK

1 . A method for execution by a dispersed storage and task (DST) processing unit that includes a processor, the method comprises:

executing a modification of a first locally cached item;

generating a first cache broadcast for transmission via a network to a plurality of additional DST processing units in response to executing the modification;

generating revision data by evaluating a first local revision level of a second locally cached item; and

executing an update of the second locally cached item when the revision data indicates that the second locally cached item is outdated.

2 . The method of claim 1 , wherein the first locally cached item includes at least one of: a data object, an index node of a dispersed hierarchical index, or an encoded data slice.

3 . The method of claim 1 , wherein the first cache broadcast includes at least one of: the first locally cached item or an item identifier corresponding to the first locally cached item.

4 . The method of claim 1 , wherein the first cache broadcast includes at least one of: a second local revision level corresponding to the first locally cached item or a timestamp associated with the modification.

5 . The method of claim 1 , wherein the revision data is generated in response to at least one of: receiving an access request or interpreting an access prediction to indicate that access is likely.

6 . The method of claim 1 , further comprising:

receiving a second cache broadcast via the network from one of the plurality of additional DST processing units, wherein the second cache broadcast includes a non-local revision level associated with the second locally cached item;

wherein generating the revision data includes comparing the first local revision level to the non-local revision level.

7 . The method of claim 6 , wherein the revision data indicates that the second locally cached item is outdated when the first local revision level compares unfavorably to the non-local revision level.

8 . The method of claim 6 , further comprising:

receiving a plurality of second cache broadcasts from the plurality of additional DST processing units;

wherein generating the revision data includes comparing the first local revision level to a plurality of non-local revision levels included in the received plurality of second cache broadcasts.

9 . The method of claim 1 , wherein executing the update includes determining a time frame to perform the update and performing the update in the determined time frame.

10 . The method of claim 1 , wherein executing the update includes:

generating a request for a current version of the second locally cached item for transmission via the network to one of the plurality of additional DST processing units;

receiving the current version of the second locally cached item from the one of the plurality of additional DST processing units via the network in response; and

updating the second locally cached item based on the received current version.

11 . A processing system of a dispersed storage and task (DST) processing unit comprises:

at least one processor;

a memory that stores operational instructions, that when executed by the at least one processor cause the processing system to:

execute a modification of a first locally cached item;

generate a first cache broadcast for transmission via a network to a plurality of additional DST processing units in response to executing the modification;

generate revision data by evaluating a first local revision level of a second locally cached item; and

execute an update of the second locally cached item when the revision data indicates that the second locally cached item is outdated.

12 . The processing system of claim 11 , wherein the first locally cached item includes at least one of: a data object, an index node of a dispersed hierarchical index, or an encoded data slice.

13 . The processing system of claim 11 , wherein the first cache broadcast includes at least one of: the first locally cached item or an item identifier corresponding to the first locally cached item.

14 . The processing system of claim 11 , wherein the first cache broadcast includes at least one of: a second local revision level corresponding to the first locally cached item or a timestamp associated with the modification.

15 . The processing system of claim 11 , wherein the revision data is generated in response to at least one of: receiving an access request or interpreting an access prediction to indicate that access is likely.

16 . The processing system of claim 11 , wherein the operational instruction, when executed by the at least one processor, further cause the processing system to:

receive a second cache broadcast via the network from one of the plurality of additional DST processing units, wherein the second cache broadcast includes a non-local revision level associated with the second locally cached item;

wherein generating the revision data includes comparing the first local revision level to the non-local revision level.

17 . The processing system of claim 16 , wherein the revision data indicates that the second locally cached item is outdated when the first local revision level compares unfavorably to the non-local revision level.

18 . The processing system of claim 16 , wherein the operational instruction, when executed by the at least one processor, further cause the processing system to:

receive a plurality of second cache broadcasts from the plurality of additional DST processing units;

wherein generating the revision data includes comparing the first local revision level to a plurality of non-local revision levels included in the received plurality of second cache broadcasts.

19 . The processing system of claim 11 , wherein the operational instruction, when executed by the at least one processor, further cause the processing system to:

generate a request for a current version of the second locally cached item for transmission via the network to one of the plurality of additional DST processing units;

receive the current version of the second locally cached item from the one of the plurality of additional DST processing units via the network in response; and

update the second locally cached item based on the received current version.

20 . A non-transitory computer readable storage medium comprises:

at least one memory section that stores operational instructions that, when executed by a processing system of a dispersed storage network (DSN) that includes a processor and a memory, causes the processing system to:

execute a modification of a first locally cached item;

generate a first cache broadcast for transmission via a network to a plurality of additional DST processing units in response to executing the modification;

generate revision data by evaluating a first local revision level of a second locally cached item; and

execute an update of the second locally cached item when the revision data indicates that the second locally cached item is outdated.