User Guide

  • 2020
  • 06/18/2020
  • Public Content
Contents

Vectorization Advisor - Analysis Summary

Vectorization Summary Purpose and Usage

After running Intel® Advisor analyses (Survey, Trip Counts, FLOPS, Memory Access Patterns, Dependencies, and Suitability), consider reviewing a results summary that includes the most important information about your code. Click the
Summary
tab after running an analysis to view results.

Vectorization Summary Report Regions

  • Program metrics
    : View the main performance metrics of your program, such as execution time statistics, vector instruction set (and whether extensions, such as VNNI, are used), and number of CPU threads utilized. The section is broken down into several sub-sections:
    • Performance characteristics
      : View execution time details, such as total CPU time and time spent in vectorized and scalar code.
      If your application uses Intel® Math Kernel Library (Intel® MKL), you will see the
      MKL detail
      button in the
      Performance characteristics
      section, which toggles two additional columns: the
      User
      column, which reports time spent in your code and corresponding compute metrics, and the
      MKL
      column, which reports time spent in the MKL code and corresponding compute metrics.
    • Vectorization Gain/Efficiency
      : View average estimated speedup of vectorized loops and total estimated program speedup.
      The vectorization efficiency data is available only for vectorized loops in modules compiled with an Intel® compiler version 16 or higher.
    • OP/S and Bandwidth
      : View GFLOPS and GINTOPS usage and cache bandwidth metrics compared to hardware peak. Hover the mouse over the
      Utilization
      column and click the button to select single-core or multicore benchmarks utilization metrics.
      The OP/S and bandwidth metrics are available after you run the Trip Counts and FLOP or the Roofline analysis.
  • Per program recommendations:
    View suggested changes for your program that you might want to apply to achieve better performance.
  • Top time-consuming loops
    : View top five time-consuming loops sorted by
    self time
    with performance metrics, such as execution time statistics and vectorization efficiency with comparison to original scalar loop efficiency.
  • Refinement analysis data
    : View details about found dependencies and memory access patterns.
    The
    Dependencies
    column summarizes the predicted data sharing problems collected by the Dependencies tool. To display the
    Dependencies Report
    window at the corresponding parallel site location, click a function link in the
    Site Location
    column.
    The
    Strides Distribution
    column reports the memory access stride distribution within a loop in the ratio format in %: unit strides, constant strides, and variable strides.
    The information in the
    Refinement analysis data
    section is available only after you run the Memory Access Patterns or Dependencies analysis.
  • Recommendations
    : View suggested changes with high confidence level for first five loops in the code that you might want to apply to achieve better performance. Click a recommendation link to access the recommendations texts.
  • Collection details
    : View execution statistics for each of the collectors, as well as the
    Collection Log
    ,
    Application Output
    , and
    Collection Command Line
    links that lead to the corresponding report logs, command line and output details.
    Application Output
    is available if you set output destination to Application Output window. To do this, go to
    File
    Options
    General
    Application Output Destination
    and choose
    Application Output window
    .
  • Platform information
    : View the system information including software and hardware summary.

Product and Performance Information

1

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.

Notice revision #20110804