[Admiral]

Для поставленной можно использовать ProcessPriorityClass

Код:

using System;
using System.Diagnostics;

class MainClass
{
    public static void Main()
    {
        Console.WriteLine("Press enter whene ready for chache my priority");
        Console.ReadLine();
        Process thisProc = Process.GetCurrentProcess();
        thisProc.PriorityClass = ProcessPriorityClass.High;
        Console.WriteLine("    new priority class: {0}", thisProc.PriorityClass);
        Console.ReadLine();
    }
}

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