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how advanced users can leverage program responsiveness and overall
the command line to manage system performance. Chapter Seven: Operating Systems
processes on Linux. Explain the
benefits and potential challenges There are several CPU scheduling
of this approach. algorithms, including the following three:
FOR ONLINE READING ONLY
(a) First Come First Served (FCFS):
CPU/Processor scheduling Like a waiting line, processes are

CPU scheduling is about ensuring served in the order they arrive. It’s
keeping the computer operations running fair but can be slow if short processes
smoothly. Imagine a busy teacher’s office. get stuck behind long ones.
Students (processes) need to be served by (b) Shortest Job First (SJF): Prioritises
the teacher (use the CPU) efficiently. CPU the shortest processes, leading to
scheduling is like the teacher, ensuring faster completion times on average.
everyone gets their fair share of CPU However, it requires knowing the
time without chaos. But what happens if process lengths beforehand, which
students get stuck waiting for each other’s isn’t always possible.
teacher? Specifically, suppose one student (c) Round Robin (RR): Acts like a fair
is being served by the first teacher while organiser, ensuring that each process
waiting for the services from the second gets a turn for the CPU usage for
teacher, and another student is being a short period before switching to
served by Teacher Two while waiting for others. The RR algorithm has several
the services of the first osne. This creates benefits, including the following
a deadlock. In the context of an operating three. The first benefit is fairness,
system, a deadlock happens when multiple because each process gets a chance
processes are waiting for resources held to run for a short time, even if it is
by each other. For example, a deadlock a long process overall. The second
might happen when one process happens
to be holding one computer resource benefit of RR is responsiveness, in a
(such as, CPU time) while waiting for a sense that short processes can finish
resource (like, memory) held by another quickly, and users experience better
process to continue execution. If two or responsiveness. The third benefit
more processes find themselves in such of RR is that it prevents starvation.
a situation, then the computer will likely Unlike FCFS, in RR shorter
stop working smoothly. Thus, because processes do not get stuck behind
programs need CPU resources to execute, long ones. Every process eventually
CPU scheduling helps to decide which gets the CPU time, even if it is for
process gets the CPU next, impacting short bursts.

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Student’s Book Form Five

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