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- Departing jobs leave their space free
- New job (from queue) must be able to fill the space (i.e. must be either
of smaller or same size as the departing job).
- Holes created in memory
- The idea of combining holes or slots together = Compaction
- Compaction : Move all occupied areas of store to one end - leaving one
large free space for incoming jobs, instead of numerous small ones
- Must be performed on each new allocation of job to memory or
completion of job from memory
- System must also maintain relocation information
- Wasteful of CPU ? Can take a long time to just do compaction and not any
serious computation
- Also called - Garbage Collection - hours on early computers
![figure94](img6.gif)
Figure 6: Storage Compaction
Omer F Rana
Tue Feb 11 19:21:10 GMT 1997