Difference between revisions of "DPS921/Intel Advisor"

From CDOT Wiki
Jump to: navigation, search
(Intel Roof-line Analysis)
(Intel Dependencies Analysis)
Line 26: Line 26:
  
 
== Intel Dependencies Analysis ==
 
== Intel Dependencies Analysis ==
 +
The compiler will be unable to vectorize loops if there are potential data dependencies. The dependencies analysis will create a dependencies report that shows where possible data dependencies exist. The report will also have details about the type of dependency and how to solve the dependency.
  
 
== Sources ==
 
== Sources ==

Revision as of 16:40, 24 November 2020

Intel Advisor

Intel Advisor is a set of tools used to measure the performance of an application.

Group Members

saketepe

Anojan Sothilingam

Intel Roof-line Analysis

The roofline tool creates a tool line model, to represent an application's performance in relation to hardware limitations, including memory bandwidth and computational peaks. To measure performance we use 2 axes with GFLOPs (Giga Flops/sec) on the y-axis, and AI(Arithmetic Intensity(FLOPs/Byte)) on the x-axis both in log scale, with this we can begin to build our roof-line. Now for any given machine, its CPU can only perform so many FLOPs so we can plot the CPU cap on our chart to represent this. Like the CPU a memory system can only supply so many gigabytes, we can represent this by a diagonal line(N GB/s * X FLOPs/Byte = Y GFLOPs/s). (pic) This chart represents the machine's hardware limitation, and it's best performance at a given AI

Every function, or loop, will have specific AI, when ran we can record its GFLOPs Because we know Its AI won't change and any optimization we do will only change the performance, this is useful when we want to measure the performance of a given change or optimization.

Intel Sustainability Analysis

Intel Survey Analysis

A Survey analysis will create a Survey Report that outlines instances:

• Where vectorization or parallelization will be most effective

• Describe if vectorized loops are beneficial or not

• Un-vectorized loops and explain why they have been Un-vectorized

• Provide general performance issue

Intel Dependencies Analysis

The compiler will be unable to vectorize loops if there are potential data dependencies. The dependencies analysis will create a dependencies report that shows where possible data dependencies exist. The report will also have details about the type of dependency and how to solve the dependency.

Sources

https://www.youtube.com/watch?v=h2QEM1HpFgg - Roofline Analysis in Intel Advisor tutorial

https://software.intel.com/content/www/us/en/develop/articles/intel-advisor-roofline.html - Intel Advisor tutorial:roofline

https://software.intel.com/content/www/us/en/develop/documentation/advisor-user-guide/top/survey-trip-counts-flops-and-roofline-analyses/survey-analysis.html