Resource Allocation Techniques for Processes

Resource Allocation

The management of how processes get and use system resources to maximize efficiency, prevent deadlocks, and ensure fair access.

Types of Resources

Categories of resources managed by operating systems including CPU cycles, memory space, I/O devices, files, and locks/semaphores.

CPU Cycles

The processing time available from the Central Processing Unit for executing processes.

Memory Space

The RAM needed for processes to run.

I/O Devices

Hardware such as printers, scanners, and disk drives used for input/output operations.

Deadlock

A situation where a set of processes is blocked indefinitely because each is waiting for a resource held by another.

Mutual Exclusion

A necessary condition for deadlock; at least one resource must be held in a non-shareable mode.

Hold and Wait

A necessary condition for deadlock; a process holding at least one resource waits to acquire additional resources.

No Preemption

A necessary condition for deadlock; resources cannot be forcibly taken away from a process.

Circular Wait

A necessary condition for deadlock; a group of processes exists where each is waiting for a resource held by the next.

Deadlock Prevention

Strategies to prevent the occurrence of deadlocks by ensuring at least one necessary condition cannot occur.

Banker's Algorithm

A deadlock avoidance algorithm requiring processes to declare their maximum resource needs, ensuring safe state allocation.

Deadlock Detection

The process of periodically checking for cycles in a resource-allocation graph to identify deadlocks.

Recovery from Deadlock

Actions taken to resolve a detected deadlock, including process termination and resource preemption.

Ignoring Deadlocks

A strategy where operating systems overlook deadlocks due to their rarity, accepting system restarts as a solution.