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→Performance Analysis
== How to Use it? ==
Before you jump into running Intel's VTune Profiler you need to make sure you run visual studio as Administrator to give it access to your hardware information, otherwise it will not be able to optimize for your specific hardware and the data collected with be very limited. Then to open Vtune press the menu as indicated below [[File:Header.png]] this will open this menu, [[httpsFile://softwareBenchmarking menu.intelpng]] allowing you to make changes to the application parameters in the centre box or just inherit the settings from Visual studio's settings, The Algorithm is currently set to HotSpot detection.com/content/dam/dita/develop/vtune '''HotSpot detection settings include:''' '''User-help-oct21/F81452C4-51AE-4AF7-B1F4-1E4C834EB757mode sampling:'''includes only for this current program and is for testing code efficiency (regardless of other processes) '''Hardware event based sampling:'''includes all processes running on the current system. pressing the dropdown menu on the Algorithm will show all the features available to VTune [[File:Settings.png/_jcr_content/renditions/original]] Pressing the play button will start the benchmarking.
== Performance Analysis ==
Running the HotSpot analysis brings up this summary after the code finishes executing.
[[File:SummaryJ.png]]
This displays the time it took for the program to execute, what active thread took the longest, what task took the longest, how much your CPU was utilized, and (not pictured here) your run parameters and CPU info (what model CPU this test was performed on).
[[File:EfCPU.png]]
The CPU effective graph indicates how many threads the program used and it's poor,ok, and ideal performance segments can be adjusted to match the desired utilization in terms of max number of threads used at anytime (and anything over ideal would be considered over-utilization).
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Pressing any of the tasks (or the bottom-up tab at the top) will bring up the bottom-up menu as shown below.
[[File:Bottom-up.png]]
This displays the actual times spent on each thread and if you selected a task when that task takes place.
The CPU time is also displayed here and the brown section indicates how much each (sample rate) section used the CPU in terms of % of total utilization of the program.
Pressing the highlighted button expands to show what % of the process uses the CPU in the ideal amount (as set on the summary screen) as shown below.
[[File:Bt-up-expand1.png]]
Pressing the highlighted button further expands the data to show in a more detailed fashion how the CPU usage is. As shown below.
[[File:Bt-up-expand2.png]]
== Microarchitecture Analysis==
This gives you an idea how efficiently the code is running on your hardware.
An interesting discovery made using this tool is that with Optimization enabled it actually utilizes the CPU less efficiently although it runs faster.
With
[[File:Micro.png]]
Without
[[File:Micro2.png]]
== History ==
The result history can be seen on the menu on the right, this will allow you to compare previous results.
[[File:Result history.png]]
== Sources ==
# [https://software.intel.com/content/www/us/en/develop/tools/vtune-profiler.html Intel VTune Profile]
# [https://software.intel.com/content/www/us/en/develop/documentation/vtune-help/top/launch/getting-started.html Installation and Features]
