Memory allocation and task priority are two entire different beasts. In a preemptive multitasking system like Windows, the task priority determines how long a program gets to execute until the operating system hands over processing to another program.. Upping the priority can allow a program to complete it's task faster but at the expense of other running applications which now receive less processor time. Thus, as Tirjasdyn says, increasing it too much may cause other applications to appear unresponsive since they simply aren't getting enough time to execute. Changing task priority AFAIK, does nothing to affect memory allocation. On the Mac, you can adjust how much memory gets allocated to an individual application so references you see to that are Mac only. Window's memory manager handles memory allocation automatically.

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