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Operating Systems | Properties of Synchronization Mechanisms

Necessary conditions to consider a synchronization method as reliable.

Properties which will enhance the efficiency of synchronization mechanisms.


Mutual Exclusion

Mutual exclusion is a property, that provides an isolation between processes from accessing critical resources simultaneously.

A process, that is using shared resources for execution of critical section, will prevent other programs from accessing the same resources with the help of synchronization mechanisms.


Progress

If selection of a process from processes, that are ready to accesses certain shared resource, get decided within a limit of time, means there is a progress in work with the method used for synchronization.

An infinite decision time show lack of progress.


Bounded Waiting

There exist a bound or a limit, if it is possible to count the number of processes, after which the request of a process to enter into critical section will be granted.

An unbounded waiting is called starvation, the prolonged waiting for requested resource.


Portability

A synchronization solution is portable, if can resolve problems independent of hardware on which it executes.


A synchronization method which continuously check whether the access to enter into critical section is called busy waiting synchronization method. Whereas methods which have sleep mode provisions are no Busy Waiting solutions.

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