Tutorial

  • 2021.1
  • 12/04/2020
  • Public Content

Roofline Use Case

This topic is part of a
tutorial
that shows how to use the automated
Roofline
chart to make prioritized optimization decisions.
The Roofline analysis is an optional analysis that plots an application's
achieved performance
and
arithmetic intensity
against the machine's
maximum achievable performance
.
Use the
Roofline
chart to answer the following questions:
  • What is the maximum achievable performance with your current hardware resources?
  • Does your application work optimally on current hardware resources?
  • If not, what are the best candidates for optimization?
  • Is memory bandwidth or compute capacity limiting performance for each optimization candidate?
Roofline analysis is cache-aware; it measures all memory subsystem traffic, not just DDR memory traffic. It works on both single-threaded and multithreaded code.
Follow these steps to use the
Vectorization Advisor
and the
roofline_demo_samples
C++ sample application to:
  • Run a Roofline analysis.
  • Focus on the
    Roofline
    chart data of most interest.
  • Interpret
    Roofline
    chart data.
  • Use
    Roofline
    chart data interpretations to make optimization decisions.
Step
Step Detail
Step 1: Prepare for tutorial.
Do one of the following:
  • Run a Roofline Analysis.
  • Show/hide the
    Roofline
    chart.
  • Get to know
    Roofline
    chart controls.
  • Get to know
    Roofline
    chart data.
  • Open a result snapshot.
  • Use various controls to focus on
    Roofline
    chart data of most interest.
  • Interpret
    Roofline
    chart data.
  • Open a result snapshot.
  • Use various controls to focus on
    Roofline
    chart data of most interest.
  • Interpret
    Roofline
    chart data.
  • Open a result snapshot.
  • Use various controls to focus on
    Roofline
    chart data of most interest.
  • Interpret
    Roofline
    chart data.

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.