CPSC 3220 - DAY 12
OCTOBER 12, 2017

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Deadlocks
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Resource: a physical or virutal entity that can be assigned to a user or
application.
	-Anything needed by a thread to do its job (CPU, disk space, memory,
	lock)
	-Preemptable: can be taken away by OS
	-Non-preemptable: must leave with thread

Starvation: thread waits indefinitely

Deadlock: circular waiting for resources
	-Deadkock => starvation.

Necessary Conditions for Deadlock
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Limited access to resources
	-If infinite resources, no deadlock!

No preemption
	-If resources are virtual, can break deadlock

Multiple independend requests
	-wait while holding

Circular chain of requests