ult upper limit for a given thread to remain inside a critical region is two seconds. Despite the fact that there are two seconds of leeway provided before two threads can dangerously enter a critical region, it is important to only protect as small a portion of code as necessary with a critical region.</p>
<p>Under Max 4.1 and earlier there was a simple protective mechanism called "lockout" that would prevent the scheduler from interrupting the low priority thread during sensitive operations such as sendin