Intel® Advisor User Guide

User Guide

Contents

Vectorization Accuracy Levels in Command Line

For each perspective,
Intel® Advisor
 has several levels of collection accuracy. Each accuracy level is a set of analyses and properties that control what data is collected and the level of collection details. The higher accuracy value you choose, the higher runtime overhead is added.
In CLI, each accuracy level corresponds to a set of commands with specific options that you should run one by one to get a desired result.
The following accuracy levels are available:
Comparison / Accuracy Level
Low
Medium
High
Overhead
1.1x
5 - 8x
10 - 40x
Goal
Get basic insights about how well your application is vectorized and how you can improve vectorization efficiency
Get more insights about how well your application is vectorized and the number of iterations in loops/functions
Get detailed insights about your application performance, including performance issues and detailed optimization recommendations
Analyses
Survey
Survey + Characterization (Trip Counts)
Survey + Characterization (Trip Counts, FLOP, Call Stacks) + Memory Access Patterns
Result
Basic Survey report
Survey report extended with trip count data
Extended Survey report with trip counts and floating-point and integer operations (FLOP and INTOP)
Memory Access Patters with memory traffic data and memory usage issues
You can generate commands for a desired accuracy level from the
Intel Advisor
 GUI. See Generate Command Lines from GUI for details.
There is a variety of techniques available to minimize data collection, result size, and execution overhead. Check Minimize Analysis Overhead .
Consider the following command examples.
Note
: In the commands below, make sure to replace the
myApplication
 with your application executable path and name
before
 executing a command. If your application requires additional command line options, add them
after
 the executable name.

Low Accuracy

To run the
Vectorization and Code Insights
 perspective with the low accuracy: 
advisor --collect=survey --project-dir=./advi_results -- ./myApplication

Medium Accuracy

To run the
Vectorization and Code Insights
 perspective with the medium accuracy:
  1. Run the Survey analysis: 
    advisor --collect=survey --project-dir=./advi_results -- ./myApplication
  2. Run the Trip Counts analysis: 
    advisor --collect=tripcounts --enable-data-transfer-analysis --project-dir=./advi_results -- ./myApplication

High Accuracy

To run the
Vectorization and Code Insights
 perspective with the high accuracy:
  1. Run the Survey analysis: 
    advisor --collect=survey --project-dir=./advi_results -- ./myApplication
  2. Run the Trip Counts and FLOP analysis: 
    advisor --collect=tripcounts --flop --stacks --project-dir=./advi_results -- ./myApplication
  3. Run the Memory Access Pattern analysis for the loops that have the
    Possible Inefficient Memory Access Pattern
     issue: 
    advisor --collect=map --select=has_issue --project-dir=./advi_results -- ./myApplication
You can view the results in the
Intel Advisor
 GUI or generate an interactive HTML report.

Product and Performance Information

1

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