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Deadlocks
Introduction to Deadlocks
Deadlock Prevention
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*Property of STI J0024
Deadlock
condition wherein a set of processes cannot continue executing because each process is waiting for a resource that is being held or used by another process within the set
Figure 7.1 Example of a Deadlock
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*Property of STI J0024
Figure 7.2 Example of a Deadlock Using a Wait-For Graph
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*Property of STI J0024
Figure 7.3 Traffic Deadlock
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*Property of STI J0024
Necessary conditions for a deadlock:
Mutual exclusion
Hold and wait
No preemption
Circular wait
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*Property of STI J0024
Deadlocks can be prevented by removing at least one of the four conditions:
Removing the mutual exclusion condition
Removing the hold and wait condition
Removing the no preemption condition
Removing the circular wait condition
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