| OCR Text |
Show Brj-...r. «9 «A 2. Segment and Process Control a. Segments In the FLEX operating environment the basic logical structure and the basic physical structure are one and the same: The segment. Logically, the segment is a contiguous string of 16-bit words in core memory and secondary storage whose length may be changed with varying degrees of effort. Addressing in the system is relative to the segment not to any particular memory location so that a particular segment may be moved anywhere without disturbing access t to it. segment | displacemenF Typical Segment Address ' Cor^' Memory High speed memory initially consists of one segment called garbage. All other segments, in the system are created by portioning the garbage. An attempt is made by the system to intersperse garbage segments between active segments. This allows some expansion without rearrangement of other ■segments. This strategy will work well with relatively static entities like process descriptions (code), and arrays. Process stacks are another matter and some shuffling is required. •\ |
