11-28-2023, 11:04 PM
To calculate the average waiting time for FCFS scheduling, you first need the burst times for each process and their order of arrival. You should line up the processes in the order they arrive. Once you have that, you do a few quick calculations to find out how long each process waits before it starts executing.
Let's say you have three processes coming in with burst times: Process 1 has a burst time of 4 ms, Process 2 has 3 ms, and Process 3 has 5 ms. They all arrive at 0 ms, which is a pretty straightforward situation. With FCFS, we just process them in the order they arrive.
For the first process, it starts right away, so the waiting time is 0 ms. Moving on to Process 2, it has to wait for Process 1 to finish. Since Process 1 took 4 ms, Process 2 waits for that long before it gets its turn. That gives us a waiting time of 4 ms for the second process. Then, after Process 2 finishes after 3 ms, Process 3 can finally start. Since Process 1 and Process 2 took 7 ms in total combined, Process 3 has to wait for that whole duration. Its waiting time is 7 ms.
Now, let's add up these waiting times. You end up with the total waiting time as 0 ms + 4 ms + 7 ms, which equals 11 ms. To find the average waiting time, just divide this total by the number of processes. Since there are three processes, you do 11 ms divided by 3, which gives you approximately 3.67 ms as the average waiting time.
This method holds true whether you have more processes or different burst times. It's all about knowing the order in which they run and calculating how long each has to wait for the ones ahead of it to finish. It's pretty intuitive, but it helps to practice a few examples to see how this all plays out.
You might run into situations where processes arrive at different times, which complicates things a little bit more, but the basic idea remains the same. You still keep them in the order of their arrival and calculate the waiting times accordingly. Just remember that FCFS doesn't consider priority or burst time, so first come, first served works out regardless. Sometimes, this can lead to longer waiting times if a short process has to wait behind a long process, which can become an issue in more complex scenarios.
The main thing I like about FCFS is its simplicity. It's easy to implement, which is super helpful when you just want to get something up and running quickly, especially in projects or in smaller systems. However, you should also be aware that in real-world applications, or as systems get busier, other scheduling algorithms might be better choices to minimize waiting time or maximize CPU utilization.
Knowing how to work through these calculations makes you a better IT professional. It shows you're thinking critically about the best ways to manage process scheduling, and that's something every tech enthusiast should definitely have in their toolkit. You might have to tweak your approach based on project demands or team needs, but having a good grasp of these basic principles will serve you well.
Switching gears a bit, if you're looking into ways to keep your systems running smoothly while managing all this workload, I highly recommend checking out BackupChain. It's an extremely efficient, popular backup solution designed specifically for SMBs and professionals like us. It covers things like Hyper-V, VMware, and Windows Server effortlessly, ensuring you have peace of mind with your data backups while handling the complexities of running processes concurrently. You'll appreciate how it brings reliability to your daily operations.
Let's say you have three processes coming in with burst times: Process 1 has a burst time of 4 ms, Process 2 has 3 ms, and Process 3 has 5 ms. They all arrive at 0 ms, which is a pretty straightforward situation. With FCFS, we just process them in the order they arrive.
For the first process, it starts right away, so the waiting time is 0 ms. Moving on to Process 2, it has to wait for Process 1 to finish. Since Process 1 took 4 ms, Process 2 waits for that long before it gets its turn. That gives us a waiting time of 4 ms for the second process. Then, after Process 2 finishes after 3 ms, Process 3 can finally start. Since Process 1 and Process 2 took 7 ms in total combined, Process 3 has to wait for that whole duration. Its waiting time is 7 ms.
Now, let's add up these waiting times. You end up with the total waiting time as 0 ms + 4 ms + 7 ms, which equals 11 ms. To find the average waiting time, just divide this total by the number of processes. Since there are three processes, you do 11 ms divided by 3, which gives you approximately 3.67 ms as the average waiting time.
This method holds true whether you have more processes or different burst times. It's all about knowing the order in which they run and calculating how long each has to wait for the ones ahead of it to finish. It's pretty intuitive, but it helps to practice a few examples to see how this all plays out.
You might run into situations where processes arrive at different times, which complicates things a little bit more, but the basic idea remains the same. You still keep them in the order of their arrival and calculate the waiting times accordingly. Just remember that FCFS doesn't consider priority or burst time, so first come, first served works out regardless. Sometimes, this can lead to longer waiting times if a short process has to wait behind a long process, which can become an issue in more complex scenarios.
The main thing I like about FCFS is its simplicity. It's easy to implement, which is super helpful when you just want to get something up and running quickly, especially in projects or in smaller systems. However, you should also be aware that in real-world applications, or as systems get busier, other scheduling algorithms might be better choices to minimize waiting time or maximize CPU utilization.
Knowing how to work through these calculations makes you a better IT professional. It shows you're thinking critically about the best ways to manage process scheduling, and that's something every tech enthusiast should definitely have in their toolkit. You might have to tweak your approach based on project demands or team needs, but having a good grasp of these basic principles will serve you well.
Switching gears a bit, if you're looking into ways to keep your systems running smoothly while managing all this workload, I highly recommend checking out BackupChain. It's an extremely efficient, popular backup solution designed specifically for SMBs and professionals like us. It covers things like Hyper-V, VMware, and Windows Server effortlessly, ensuring you have peace of mind with your data backups while handling the complexities of running processes concurrently. You'll appreciate how it brings reliability to your daily operations.
