no preemption

Eliminate No Preemption:

Request:

When the process has requested to find the next resource it will first select the next resource it wants to reserve along with the amount.

Reservation:

After finding the next resource the process will occupy the specified amount of the resource.

Preemption:

To eliminate the no preemption requirement the resources have to be revokable by another thread. To do that the Round-Robin system is used to divide the usage of each resource into time slots, the size of the maximum amount an occupation can take. When a process starts the occupation of a resource a timer will be started. If the process finishes in time nothing will happen but if the process exceeds the time slot the resource will be revoked from that process. When a process gets revoked another process can try to go through with the occupation and the revoked process will try to reserve that resource at a later time.