Package com.bigdata.resources

This package provides the logic to managed the live journal and the historical journals and index segments for a DataService.

See: Description

Package com.bigdata.resources Description

This package provides the logic to managed the live journal and the historical journals and index segments for a DataService.

Overflow actions (Split, Join, Move, Build, Merge, etc.)

The critical distinction among the actions is whether or not they change the index partition identifier, in which case they define a new index partition. OverflowActionEnum#Copy, OverflowActionEnum#Build and OverflowActionEnum#Merge are "actions" which DO NOT change the index partition identifier.

For actions which define a new index partition, the critical distinction is whether the action is 1:N (OverflowActionEnum#Split) or N:1 (OverflowActionEnum#Join). Note that both OverflowActionEnum#Split and OverflowActionEnum#Join can conceptually locate the new index partition(s) on different data service(s). OverflowActionEnum#Move DOES change the index partition identifier and is in effect a 1:1 action. Since the locator for an index partition MUST NOT change, MOVE serves to "rename" an index partition, and in the process relocates it on another data service.

Neither OverflowActionEnum#Split nor OverflowActionEnum#Join is restricted to operate on only the local index partitions. The critical constaint when writing these operations is that they MUST hold exclusive write locks on the source index partition(s) such that the change in the index partitions can be made atomic. However, the manner in which the operation proceeds does differ when some of the output partition(s) will be located on a different data service. It is also more complex when some of the input partition(s) will be located on a different data service as the write lock must be coordinated across two or more data services.

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