Preemptive Shortest Job First (PSJF)

Process	arrival	long process
A B C D E	0 0 0 0 0	7 10 2 4 8

Preview Case I - a queue of five process with arrival = 0

process	arrival	long process
A B C D E	0 1 8 2 5	7 10 2 4 8

Preview Case II - a queue of five different process arrival

Preemptive Shortest Job First (PSJF) also known as Shortest Process engineering Dipertamakan Preempsi (PTDP). PSJF is the scheduling priority and with preempsi. Priority is based on short rest process. Short rest of the process of getting a higher priority. Furthermore, with this provision, when it arrived, the shortest in the back of the queue does not just move to the front of the queue, but also through preempsi, issuing process at that time was in the process (if any).
Used two steps to see the implementation of this scheduling. First step: each time, pay attention to when the process arrives or when the process finished. Step two: calculate the time remaining processes of all the processes that existed at that time. If there is a process with rest of the process is shorter than the rest of the process on the process that is being done, so on the basis preempsi, a process that is being done is taken out of the processor. Instead, the process with the shortest remaining is what is done by the processor.
Here the question arises. What if the process that it has long arrived following the same process with the remaining processes on existing processes. Is preempsi happen too? If the old process or the rest of the process is the same, then the treatment is set according to the order of the existing queue.
For clarity, let's see an example in the case II we find a set of processes with different arrival as shown in Figure below.

Name Process	Arrival	long process	start	finish	time futile	long perceptive
A B D E C	0 1 2 5 8	7 10 4 8 2	0 21 7 13 11	7 31 11 21 13	0 20 5 8 3	7 30 9 16 5
				average	36 7,2	67 13,4

 Preview performance of the processor with algorithms for case II PSJF