| OCR Text |
Show L, ^M-.^V".-« ... ; ■ 85 The real-time processes, the event list, the segment table, and other system entities need to maintain residency in primary storage all of the time. Therefore, they should never be swapped,. 0- 2 0' 3(r 40" oy-, Priority: 12 3 4 These priorities may be expressed as a v/eighted conditional probability or as the number of standard (■fc) deviations on a normal curve. The swapping scheme now works as follows, A random number is selected just $s in segment creation. This is hashed to locate a slot in the segment table and thus, eventually, a segment. The type field is examined for priority and a question is asked whose answer is weighted towards that priority. For the normal curve weighting scheme, the probability of a ;yes answer to the question: "Should this segment be swapped?" is: area of a number total area of a curve If the segment was text, then it would have a 57% probability of being swapped and a corresponding 33% chance |
