انظمة التشغيل من الشابتر5

is the execution of more than one operation simultaneously.

• Concurrency

• process

• A process requesting a service from another process

• Increasing execution speed

by dividing one large task into several processes that are executed in parallel.A process may precede other operations with it.

• Concurrency

• process

• A process requesting a service from another process

• Increasing execution speed

if it influences or is affected by other processes it works with in parallel

• Concurrency

• process is collaborative

• A process requesting a service from another process

• ncreasing execution speed

the process that requested the service must wait for the process from which the service was requested until it has finished performing it.

• Concurrency

• process

• A process requesting a service from another process

• Increasing execution speed

The scheduler in the operating system may reserve any process at any time for any reason, this reservation will stop the process currently executing in the processor, and another process enters its place.

• Unexpected Reserving of Processes

• Competition

• Dead Lock

Collaborating processes may have shared data that they have access to.

• Unexpected Reserving of Processes

• Competition

• Dead Lock

This type of resource can be stripped from the process using it without causing problems, such as memory, processor.

• Preemptive Resources

• Non Preemptive Resources

• resource

A process error may occur if the resource is stripped from it, such as a printer.

• Preemptive Resources

• Non Preemptive Resources

• resource

Only one transaction uses a particular resource at a particular moment, so no two processes can use the same resource at the same time.

• Mutual Exclusion

• Hold and Wait

• Non Preemption of the Resource

the resource cannot be extracted from the process that uses it unless its work is completed.

• Mutual Exclusion

• Hold and Wait

• Non Preemption of the Resource