Scheduling algorithms say how much time is allocated to Processes and Threads. Their goal is to fulfil a number of criteria:
All tasks should get their chance to use CPU resources.
When time to use priority, lower priority should not be starved for higher time.
The scheduler should scale well with a growing number of tasks, ideally being O(1). This is observed in the Linux kernel.
Existing Scheduling Algorithms:
These are off three types. They are:
1. Interactive Scheduling Algorithm
2. Batch Scheduling Algorithm
3. Real Time Scheduling Algorithm
1. Interactive Scheduling Algorithms:
These are off four types, they are
• Round robin Scheduling
• Priority based Round robin.
• Shortest Process Next.
• Lottery Scheduling
Round Robin Scheduling:
It is pre-emptive scheduler and the simplest algorithm. This use only a single queue of process. When the system fires, next process is switched to and the pre-empted process is set back into queue.
Each process is assigned with a time slice or ‘Quantum’. Quantum gives us the number of system timer ticks the process may run for before being pre-empted. Each process is given a Quantum, but the question is how can we choose a time quantum.
Advantages:
o It is simple and strict ‘First come First served nature.
Disadvantages:
o Absence of Priority system, because of which low privilege has to wait for higher privilege one.
Priority based Round Robin:
This is similar to Round Robin, but allows a hierarchy of process. Multiple process queues are used. As long as higher priority one is in the queue, they run first and other lower priority process waits.
Advantages:
o Its simplicity and reasonable support for priorities.
Disadvantages:
o Lower priority proces...
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... a feasible schedule. If the EDF algorithm fails to produce a feasible schedule, then no feasible schedule exists. When the goal of scheduling is to meet deadlines, there is no advantage to completing any job sooner than necessary.
Least Slack Time:
It is also called minimum laxity first
The slack time is d-t
T is the time remaining to complete the job
Example
J1 is released at time 0, its deadline is 6, and its execution time is 3
At time 0, the slack time is 3
As long as it executes, its slack remain at 3
Now suppose that it is preempted at time 2 by J3 which executes from time 2 to 4
During this interval, the slack of J1 decreases from 3 to 1
At time 4, the remaining execution time of J1 is 1
The LST algorithm assigns priorities to jobs based on their slacks
The smaller the slack the higher the priority
LST algorithm is optimal.
A state variable known as congestion window is implemented by the TCP protocol which stops the clogging of the network by regulating and putting a limit on the data that is sent on the network in turn reducing congestion, timeouts and lost packets.
The tuning strategy process parameters are designed such that they do not effect 1) the maximum throughput of multi-core processors and 2) the overall execution time of workloads. There have been experiments
Having block scheduling is one of the main concerns of the Aldine Independent School District. Block scheduling is when students have half of their classes one day and the other half the next. There has been some complaints about how block scheduling decreases students’ focus, but there has also been many compliments about how it improves students’ education. Michael D. Rettig, President of School Scheduling Associates, states that more schools are considering block scheduling and more than thirty percent of schools in the country already have it [bandwagon]. The Aldine Independent School District has made the reasons remarkably clear as to why they have switched to block scheduling and they are: better test scores, better grades, and improvement of teacher-student interaction.
Time how long it takes for the reaction to take place by timing how long it takes for the disk to
The table above shows what this ordering of instructions may look like in action. Over 8 instruction steps, the operations required by Process0 and Process1 are fully completed by sharing the single CPU resource efficiently. Normally, modern desktop computers are capable of
The inter-temporal relationship between every task was specified in advance so the impact of delay of a task on other tasks could be calculated.
After I have set my schedule, I will begin tracking my progress and manipulating the schedule accordingly. I will follow the schedule I set for the day checking to see what things I have been able to accomplish. The first few days things while be moved around and prioritized, if I find out the task I assigned myself only takes forty-five minutes instead of an hour I may cut down the time I have allowed myself accordingly. The same is true for the opposite, and if something takes me an hour and thirty minutes when I only gave myself an hour, the schedules will be changed for the next day with more time allotted to the
Critical task are those tasks which cannot be delayed in any circumstance and there is 0 slack time between the tasks means that if one task is finished the next task immediate start without any delay.
...nefit of work scheduling flexibility, in job training and reduced repetitiveness. High-quality of work: There are two motivation factors which are interrelated to encourage high-quality work performance. One is the job characteristic and the dependent factor is psychological empowerment. The plan is to enrich the job characteristics by improving skill variety, identity and significance of the task, employee independency to layout the job function and consistent job feedback which will help to create a feeling of competency and commitment to the work and thus will result in high-quality work performance. The plan is also to encourage technological innovative work and recognition based on the performance which will help to increase employee motivation and high-quality performance and reduced product defects.
Disciplined time management is fundamental to effective project management, if a project manager cannot control his own time, then the project cannot be controlled. (Kerzner, 2013). Key elements to time management are planning and prioritisation. Planning is a system in which you categorise what you need to do for a project such as determining objectives, identifying achievement steps, the breakdown of the task into components tasks, time taken and identification of what you require from others (Caunt, 2013, 27). This indicates that a plan can be likend to a process in which steps have to be clearly defined in order for it to work. Plans should always be time bound, giving the relation to time maagement, planning is as fundamental to time
Execution is a very important stage of the project life cycle. It is the third stage of the project cycle where the project plan is put into work. This is yet another very important phase of the cycle as this is where all of the work is done to achieve the output required for the project. Once a project is initiated and the project is planned out, it needs to be executed according to the plans set and expectations of the upper management and stakeholders (McGraw, 2009). The project has to be worked on according to the plans made during the initiation and planning phase of the project. Executing the project successfully very much depends on all the stakeholders who are involved in it.
When an executable file is loaded into memory, it is called a process. A process is an instance of a program in executing. It contains its current activity, such as its program code and also the contents of the processor’s register. It generally includes the process stack, which contain temporary data, and a data section, which global variables. During runtime, it may include a heap, or dynamically allocated memory. In contrast with a program, a process is “an active entity, with a program counter specifying the next instruction to execute and a set of associated resources” (Operating System Concept 106). A process is a program that executes a single instance of a thread. Multiple threads can exist which allows more than one task to perform at a time. Multithreaded processes may share resources such as code, data, and file section. They do not share resources such as registers and stack.
We determined various performance measures using recursive method and matrix method. Various probabilities are found out by using recursive method and performance measure are determined by matrix method using computer language MATLAB. Hence, with the help of these probabilities queue size has been determined and various applications have been discussed.
It provides a well organized and graceful approach to operate scale-out applications in a predictable and cost effective manner.
technology community. Artificial intelligence or AI can be seen as a futuristic form of technology