Intel® Advisor User Guide

User Guide

Contents

GPU Roofline 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
5 - 10x
15 - 20x
20 - 50x
Goal
Analyze kernels in your application running on GPU
Analyze kernels running on GPU and loops/functions running on CPU in more details
Analyze kernels running on GPU and loops/functions running on CPU in more details
Analyses
Survey with GPU profiling + Characterization (FLOP)
Survey with GPU profiling + Characterization (FLOP, memory object analysis with light data transfer simulation between host and target device memory) + Performance Modeling for a baseline GPU
Survey with GPU profiling + Characterization (Trip Counts and FLOP with call stacks for CPU, CPU cache simulation, memory object analysis with medium data transfer simulation between host and target device memory) + Performance Modeling for a baseline GPU
Result for kernels on GPU
Memory-level GPU Roofline (for CARM, L3, SLM, GTI) with basic set of recommendations for performance optimization
Memory-level GPU Roofline (for CARM, L3, SLM, GTI) with extended set of recommendations for performance optimization
Memory-level GPU Roofline (for CARM, L3, SLM, GTI) with extended set of recommendations for performance optimization
Result for loops/functions on CPU
Cache-aware CPU Roofline for L1 cache
Memory-level Roofline with call stacks (for L1, L2, L3, DRAM)
Memory-level Roofline with call stacks (for L1, L2, L3, DRAM)
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.
Info
: 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
GPU Roofline Insights
 perspective with the low accuracy: 
advisor --collect=roofline -–profile-gpu --enable-data-transfer-analysis --project-dir=./advi_results -- ./myApplication

Medium Accuracy

  1. Run the GPU Roofline. 
    advisor --collect=roofline --profile-gpu --enable-data-transfer-analysis --track-memory-objects --data-transfer=light --project-dir=./advi_results -- ./myApplication
  2. Run Performance Modeling for the GPU that the application runs on. 
    advisor --collect=projection --profile-gpu --enforce-baseline-decomposition --model-baseline-gpu --project-dir=./advi_results
    The
    --model-baseline-gpu
     option automatically enables
    --enforce-baseline-decomposition
    . To simplify the command, you can skip the
    --enforce-baseline-decomposition
     option and use only
    --model-baseline-gpu
    .

High Accuracy

  1. Run the GPU Roofline. 
    advisor --collect=roofline --profile-gpu --stacks --enable-cache-simulation --enable-data-transfer-analysis --track-memory-objects --data-transfer=medium --project-dir=./advi_results -- ./myApplication
  2. Run Performance Modeling for the GPU that the application runs on. 
    advisor --collect=projection --profile-gpu --enforce-baseline-decomposition --model-baseline-gpu --project-dir=./advi_results
    The
    --model-baseline-gpu
     option automatically enables
    --enforce-baseline-decomposition
    . To simplify the command, you can skip the
    --enforce-baseline-decomposition
     option and use only
    --model-baseline-gpu
    .
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.