1. A method comprising: allocating a quantity of processors for processing a job in a high-performance computing environment to provide an initial allocation, wherein the initial allocation of the quantity of processors for the job is allocated to at least one of: a first area of processors which is more densely occupied than a second area of processors based on a first probability indicative of a probability that the job will have an increased computing demand during the run time for the job; and a second area of processors which is more sparsely occupied than a first area of processors based on a second probability indicative of a probability that the job will have decreased computing demand during the run time for the job; and modifying the initial allocation during a run time of the job by performing one or more of: increasing the allocated quantity of processors in response to an increased computing demand for the job by allocating one or more free processors from a pool of free processors which are configured to meet the increased computing demand for the job; or decreasing the allocated quantity of processors in response to a decreased computing demand for the job by reallocating one or more processors from the allocated quantity of processors to the pool of free processors, wherein the allocated one or more free processors configured to meet the increased demand for the job are within a vicinity of the quantity of processors used to provide the initial allocation.