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Give examples of reusable and consumable resources.
Give examples of reusable and consumable resources.
Examples of reusable resources are processors, I/O channels, main and secondary memory, devices, and data structures such as files, databases, and semaphores. Examples of consumable resources are interrupts, signals, messages, and information in I/O buffers.
What are the three conditions that must be present for deadlock to be possible?
What are the three conditions that must be present for deadlock to be possible?
Mutual exclusion, hold and wait, and no preemption.
What are the four conditions that create deadlock?
What are the four conditions that create deadlock?
Mutual exclusion, hold and wait, no preemption, and circular wait.
How can the hold-and-wait condition be prevented?
How can the hold-and-wait condition be prevented?
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How can the circular wait condition be prevented?
How can the circular wait condition be prevented?
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What is the difference among deadlock avoidance, detection, and prevention?
What is the difference among deadlock avoidance, detection, and prevention?
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Mutual exclusion allows multiple processes to use a resource at the same time.
Mutual exclusion allows multiple processes to use a resource at the same time.
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Hold and wait means a process is waiting while holding at least one resource.
Hold and wait means a process is waiting while holding at least one resource.
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No preemption means resources can be forcibly taken from a process.
No preemption means resources can be forcibly taken from a process.
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What does circular wait refer to?
What does circular wait refer to?
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What are the categories of reusable resources?
What are the categories of reusable resources?
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What defines consumable resources?
What defines consumable resources?
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What is meant by a 'safe state'?
What is meant by a 'safe state'?
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What is an 'unsafe state'?
What is an 'unsafe state'?
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Study Notes
Resource Types
- Reusable Resources: Include processors, I/O channels, main and secondary memory, devices, files, databases, and semaphores. They can be safely utilized by one process at a time and are not depleted with use.
- Consumable Resources: Examples are interrupts, signals, messages, and I/O buffer information. These can be produced and consumed.
Deadlock Conditions
- Mutual Exclusion: Only one process can use a resource at any given time.
- Hold and Wait: A process may hold allocated resources while waiting for additional resources.
- No Preemption: Resources cannot be forcibly taken from a process that is holding them.
- Circular Wait: A closed loop of processes exists where each holds at least one resource needed by the next.
Deadlock Prevention and Avoidance
- Preventing Hold-and-Wait: Processes must request all required resources simultaneously and are blocked until all requests can be granted.
- Preventing Circular Wait: Define a linear ordering of resource types, allowing processes to request only those types that follow their already allocated resource.
Deadlock Management Strategies
- Deadlock Prevention: Involves constraints on resource requests to eliminate at least one of the four necessary deadlock conditions.
- Deadlock Avoidance: Allows the three necessary conditions but makes careful decisions to prevent reaching a deadlock state.
- Deadlock Detection: Periodically checks for circular wait conditions and allows resource requests whenever possible under a detection algorithm.
Resource Allocation States
- Safe State: A condition where there is at least one sequence of resource allocations to processes that avoids deadlock.
- Unsafe State: A scenario without a guarantee of avoiding deadlock, indicating potential risk in resource allocation.
Key Definitions
- Mutual Exclusion: Only one process can utilize a resource at a time.
- Hold and Wait: A process is holding resources and waiting for others.
- No Preemption: Resources cannot be preempted from any process holding them.
- Circular Wait: Represents a situation where processes form a loop, each waiting on resources from others.
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Description
Test your knowledge on Chapter 6 of Operating Systems with these flashcards. This chapter focuses on resource types and conditions for deadlock. Enhance your understanding through examples and key concepts presented in this quiz.