Creato da pastuweb.com
Share My Page
My Social Accounts
Account FaceBook Account LinkedIn Account Twitter Account Google Plus Account Git Hub

It is sometimes useful to temporarily transfer a process that is located in RAM memory out of it, and then recover it quickly(swapping).
There are some very fast disks, large enough to contain a copy of the entire secondary storage.

There are different strategies for efficient swapping.
The simplest strategy involves cycling of the active processes in turn (round robin). Other strategies are based on the prioritiesdefined by the scheduler of the processes: in this way it is possible to swap the processes with lower priority, in order to perform in a short time processes at higher priority.
Normally the system maintains a queue of processes ready to run,ie those that have an image in the backing store.
Swapping is implemented in many OS in a different way.

In UNIX systems, it becomes active only in the case in which the portion of main memory used by all the processes appears to begreater than a certain threshold.
In the early Windows systems, however, the swap is initiatedwhen you tried to run a job that was not entirely in main memory.

Average (1 Vote)
The average rating is 5.0 stars out of 5.