Segmentation



Stage 2 - want B2 in main memory


Segmentation Placement

placement: where to locate (place) a segment

  1. best fit: smallest hole (contiguous space) the segment can fit in
  2. first fit: first hole (contiguous space) the segment can fit in
  3. worst fit: largest hole (contiguous space) the segment can fit in
- this idea is perhaps good, but simulation experiments show that after a while, it tends to eliminate all large holes and only be able to satisfy requests for small holes

List of Free Spaces (free list)

  1. sort by address for first fit - so you can later combine adjacent holes together easily to form larger holes
  2. sort by size for best fit and worst fit

Replacement

  1. segment of a terminated process
  2. segment of a blocked process
  3. segment of a ready process

paging is the winning approach, wastes little space with little management overhead

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