Extension: Incomplete resource requirements a-priori knowledge 
 
 
- In the real world, tasks rarely know their resource requirements in advance.
- Less of an issue if migration is possible, more problematic if not.
- Our Idea: Approximate cost by the differential of the cost function. (The cost for a task imposing an infinitesimal consumption on each resource.)
- Results: PVM slowdown 14.08, Differential-PVM 10.7, EPVM with full knowledge 9.6.
- Implication: Although the knowledge is incomplete, managed to capture 75% of the improvement.