By default, as a job is running, the dynamic priority decreases gradually until the job has finished running, then increases immediately when the job finishes.
In some cases this can interfere with fairshare scheduling if two users who have the same priority and the same number of shares submit jobs at the same time.
To avoid these problems, you can modify the dynamic priority calculation by using one or more of the following weighting factors:
Run time decay
Historical run time decay
Committed run time