Operating System Principle : Assignment

Operating System Working Principle of
Shortest Remaining Time First Algorithm
Introduction
Shortest Remaining
Time First Scheduling
is a pre-empted
version of SJF
(Shortest Job First). In
SJF, once a process
begins execution, it
runs until it is
completed. In SRTF A
successive process
can be pre-empted
by a process of user
with a minimal
estimated run time 1.
Advantages•SRTF is a
scheduling
algorithm that
favours jobs that
can be done the
fastest
•Schedule shortest
ones first
•Optimize average
response time
•Probably optimal
with respect to
minimizing the
average waiting
time.
•The advantages of
SRTF is short
processes returns
quickly and it has
high yield2.
Disadvantage
s•it must be possible
to accurately
estimate a job's
remaining time
and large jobs may
never get their
time share if many
small process is
continually added
•Practically it is not
possible to predict
the burst time3.
Conclusion
It can be
concluded that the
shortest remaining
time first algorithm
depends on the CPU
burst time. It is the
pre-emptive version
of SJF. This algorithm
optimises the
average time.
•1. OS SRTF scheduling Algorithm - javatpoint". in , ,
2018, <https://www.javatpoint.com/os-srtf-
scheduling-algorithm> [accessed 30 October 2018].
•2. KAUR, P, "SRTF algorithm | Techtud.".
in Techtud.com, , 2018,
<https://www.techtud.com/example/srtf-algorithm-
0> [accessed 30 October 2018].
•3. "SCHEDULING ALGORITHMS". in , , 2018, <https://
www.cl.cam.ac.uk/teaching/1617/OpSystems/pdf/05-
Scheduling-Algorithms.pdf> [accessed 30 October
2018].
References