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2. Per-task Currentcy Allocations

Given the overall allocation, the next decision is how to allocate currentcy among competing tasks.

Determination of per-task share. This may reflect an external priority or criticality of the task, the energy demand of the task, or some combination. In our prior work, the share is based on a user specification, scaled to a percentage based on all tasks in the system.

Handling of unused currentcy. When a task finishes an epoch without using its allocation, what happens to the residual currentcy? Choices include forfeiting the remaining allocation at the end of the epoch, saving it all, saving up to a dynamic or static cap, or distributing it among other tasks. Techniques to redistribute unused currentcy are considered in Section 4.

Debt limits. Do we allow a task to perform deficit spending and what are the rules on paying it back?

Subaccounts. Earmarking portions of a task's allowance for use with a particular device or by a particular thread within the resource container may require richer API support (a topic of future research).
next up previous
Next: 3. Currentcy Accounting Up: Policy Building Blocks Previous: 1. Overall Currentcy Allocation
Heng Zeng 2003-04-07