<strong>Cpu Time Vs Wall Time: Which Is Better And Why?</strong>

In computing, CPU time vs wall time are measures of the amount of time a given process has consumed. The CPU time is the amount of time the process spent on the CPU, while wall time is the total elapsed time, including wait times.

When measuring performance, it is important to understand which metric you are using. CPU time is more important for measuring individual tasks, while wall clock time is more important when measuring overall system performance. In this blog post, we will discuss the differences between CPU time and wall clock time, and explain why the wall clock time is usually considered to be more important.

Wall clock time is the amount of time that has elapsed from the start of the process to the current point in time. This includes any time that the process has spent waiting for other processes to finish, or for resources to become available. For example, if a process spends 30 seconds on the CPU and 30 seconds waiting for I/O, then the wall clock time for that process is 60 seconds.

CPU time is the amount of time that the process has spent on the CPU. This does not include any time that the process has spent waiting for other processes to finish, or for resources to become available. For example, if a process spends 30 seconds on the CPU and 30 seconds waiting for I/O, then the CPU time for that process is 30 seconds.

CPU time is a more accurate measure of how much work a process has done, while wall clock time is a more accurate measure of how long a process has taken. CPU time is also less affected by delays caused by other processes or resources.

When measuring performance, it is important to understand which metric you are using. CPU time is more important for measuring individual tasks, while wall clock time is more important when measuring overall system performance. In most cases, wall clock time is considered to be more important than CPU time.

What Is The Difference Between Cpu Time And Wall Time?

Most of the time we tend to measure the time taken by a particular program or task in terms of wall time. If you are one of those who are very interested in knowing what is Cpu time and what is wall time then you are in right place.

So, let’s know the difference between these two types of time in detail.

CPU Time Vs Wall Time

When we talk about the time taken to execute a program or task, then it is referred to as wall time. It is the time that has been consumed by the process or program and it is not dependent on any other factor.

On the other hand, when we talk about the time that has been used to execute the process or task, then it is known as CPU time. CPU time is the time that is consumed by the process or task while executing and it is dependent on the number of processes running in the system.

Both of them are important but which one is better? If you ask me then I will say that CPU time is more important than wall time. But there is another reason for it and it is that wall time is not accurate. The wall clock does not count the time taken by the program or task while it is being executed.

If you have an example then imagine that your friend is calling you and you don’t want to answer it. But you have a meeting in your office and you want to go there. So, you are thinking of not answering the call, but in the meeting, you get the call and you are unable to attend the meeting. So, you are late and you will be penalized.

Now, when you are going to get the bill for that meeting, then how will the meeting time appear? It will show only the time that has been used by your phone.

Similarly, if you are checking your email, then you will get the time that has been used by the process and not the time that has been consumed by the program. But, when you are checking your browser it will show you the real-time that has been consumed by the process.

CPU Time Vs Wall Time: Which Is Better And Why?

In simple words, CPU time is the time that is used by the process or task while executing and wall time is the time that has been consumed by the process or task. Wall time is not accurate as it doesn’t count the time that is consumed by the process or task.

If you have a good example then imagine that your friend is calling you and you don’t want to answer it. But you have a meeting in your office and you want to go there. So, you are thinking of not answering the call, but in the meeting, you get the call and you are unable to attend the meeting.

So, you are late and you will be penalized. Now, when you are going to get the bill for that meeting, then how will the meeting time appear? It will show only the time that has been used by your phone.

Similarly, if you are checking your email, then you will get the time that has been used by the process and not the time that has been consumed by the program. But, when you are checking your browser it will show you the real-time that has been consumed by the process.

Conclusion

In simple words, CPU time is the time that is used by the process or task while executing and wall time is the time that has been consumed by the process or task. Wall time is not accurate as it doesn’t count the time that is consumed by the process or task.

If you have a good example then imagine that your friend is calling you and you don’t want to answer it. But you have a meeting in your office and you want to go there. So, you are thinking of not answering the call, but in the meeting, you get the call, and you