How can I change priority of that process?
prioridade de renice [-p] pid
Useful priorities are: 20 (the affected processes will run only when nothing else in the system wants to), 0 (the ''base'' scheduling priority), anything negative (to make things go very fast)
Exemplo: renice -5 -p 123
, 123 é processo PID, -5 é prioridade
Will it speedup my application processing?
Não, se a carga for menor, menor número de núcleos de CPU.