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Module 4: Deadlocks

20237m

For a deadlock to occur, each of the necessary conditions must hold. By ensuring that at least one of these conditions cannot hold, we can prevent the occurrence of a deadlock. Give one approach individually to prevent each of these necessary conditions.

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Deadlock Prevention per Condition

  1. Mutual Exclusion: make resource shareable (read-only, spooling)
  2. Hold-and-Wait: require process to request all resources at once, or release held before new request
  3. No Preemption: allow OS to preempt resources
  4. Circular Wait: impose total ordering of resource types, request in order

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