1. A best-effort parallel processing system comprising: a processing platform configured to execute application computations; an application layer that comprises applications that are executed on the processing platform; and a best-effort computation layer interfaced between the application layer and the processing platform that is configured to classify computations requested by the application layer as guaranteed computations, which are assuredly executed by the processing platform, and best-effort computations, the best-effort computation layer further configured to perform at least one of: dropping of best-effort computations despite the existence of processing performance to execute the dropped best effort computations and re-ordering of best-effort computations such that dependencies between at least two of the re-ordered computations are not maintained.