Solved: Different thread Usage between Vtune & Task Manager

Jeremy_Chen · ‎02-21-2023

Hi dev team,

I tried to use the thread mode of Intel Vtune Profiler to analyze the usage of CPU processors of my company's program.

We start collecting when task manager's CPU usage start rising to 100%, and stop once usage decreases.

But the VTune result shows that processors seldom run simultaneously, which is different from task manager.

Could you give some advice on this situation?

JyothisV_Intel · ‎02-23-2023

Hi,

Good day to you.

Thanks for posting in Intel Communities.

CPU Utilization in Windows Task Manager refers to the percentage of processing power that is being used by the central processing unit (CPU) of your computer at a given moment. It shows how much of the CPU's resources are currently being used by the active processes including the background processes or services, windows system processes or services and even the task manager itself!

The CPU utilization percentage is calculated by dividing the amount of time that the CPU is actively processing by the total time available. For example, if the CPU is processing constantly for 1 second out of every 10 seconds, the CPU utilization would be 10%.

Effective CPU Utilization in Intel VTune Profiler refers to the percentage of CPU resources that are being used to execute useful work or instructions, as opposed to idle or non-useful work. It is a performance metric that helps to identify how efficiently the CPU is being utilized by the software application being profiled.

Additionally, it also gives a idea on how effectively the profiled application is able to scale to all the logical CPU cores. This means that this number can be used as a baseline for your performance measurements. The closer this number is to the number of logical CPU cores, the better; since the profiled application is able to scale and effectively use all the cores of the CPU.

Effective CPU Utilization is calculated by dividing the amount of time that the CPU is executing useful work by the total execution time. Useful work includes any work that contributes to the application's performance, such as executing code, processing data, or handling I/O operations. Non-useful work includes idle time, time spent waiting for external events, and time spent executing overhead tasks that do not directly contribute to the application's performance.

Effective CPU Utilization Histogram in Intel VTune Profiler is a visualization tool that provides a detailed view of the distribution of CPU utilization across a range of time intervals during the execution of a software application. By examining the histogram, developers can pinpoint areas where the CPU utilization drops significantly and identify the root causes of the issue, such as inefficient algorithms or poor resource utilization.

Reference: https://www.intel.com/content/www/us/en/develop/documentation/vtune-help/top/reference/user-interface-reference/window-summary/window-summary-hotspots-by-cpu-usage.html#window-summary-hotspots-by-cpu-usage_CPU_USAGE

Hope this helps. If this clears you query, kindly mark this as a solution as it might help others with a similar issue.

Regards,

Jyothis V James

View solution in original post

JyothisV_Intel · ‎02-23-2023

Hi,

Good day to you.

Thanks for posting in Intel Communities.

CPU Utilization in Windows Task Manager refers to the percentage of processing power that is being used by the central processing unit (CPU) of your computer at a given moment. It shows how much of the CPU's resources are currently being used by the active processes including the background processes or services, windows system processes or services and even the task manager itself!

The CPU utilization percentage is calculated by dividing the amount of time that the CPU is actively processing by the total time available. For example, if the CPU is processing constantly for 1 second out of every 10 seconds, the CPU utilization would be 10%.

Effective CPU Utilization in Intel VTune Profiler refers to the percentage of CPU resources that are being used to execute useful work or instructions, as opposed to idle or non-useful work. It is a performance metric that helps to identify how efficiently the CPU is being utilized by the software application being profiled.

Additionally, it also gives a idea on how effectively the profiled application is able to scale to all the logical CPU cores. This means that this number can be used as a baseline for your performance measurements. The closer this number is to the number of logical CPU cores, the better; since the profiled application is able to scale and effectively use all the cores of the CPU.

Effective CPU Utilization is calculated by dividing the amount of time that the CPU is executing useful work by the total execution time. Useful work includes any work that contributes to the application's performance, such as executing code, processing data, or handling I/O operations. Non-useful work includes idle time, time spent waiting for external events, and time spent executing overhead tasks that do not directly contribute to the application's performance.

Effective CPU Utilization Histogram in Intel VTune Profiler is a visualization tool that provides a detailed view of the distribution of CPU utilization across a range of time intervals during the execution of a software application. By examining the histogram, developers can pinpoint areas where the CPU utilization drops significantly and identify the root causes of the issue, such as inefficient algorithms or poor resource utilization.

Reference: https://www.intel.com/content/www/us/en/develop/documentation/vtune-help/top/reference/user-interface-reference/window-summary/window-summary-hotspots-by-cpu-usage.html#window-summary-hotspots-by-cpu-usage_CPU_USAGE

Hope this helps. If this clears you query, kindly mark this as a solution as it might help others with a similar issue.

Regards,

Jyothis V James

JyothisV_Intel · ‎03-01-2023

Hi,

Good day to you.

Thanks for accepting our answer as solution. Since, your initial query is now answered, we won't be monitoring this thread further. If you need assistance while using any Intel products or services, do start a new thread. We are always happy to help.

Regards,

Jyothis V James