Intel® VTune™ Profiler User Guide

User Guide

Contents

Introduction

Intel® VTune™
Profiler
 is a performance analysis tool for serial and multithreaded applications. Use
VTune
Profiler
 to analyze your choice of algorithm. Identify potential benefits for your application from available hardware resources.
Intel® VTune™ Profiler is a new renamed version of the Intel® VTune™ Amplifier.
Use
VTune
Profiler
 to locate or determine:
  • The most time-consuming (hot) functions in your application and/or on the whole system
  • Sections of code that do not effectively utilize available processor time
  • The best sections of code to optimize for sequential performance and for threaded performance
  • Synchronization objects that affect the application performance
  • Whether, where, and why your application spends time on input/output operations
  • Whether your application is CPU or GPU bound and how effectively it offloads code to the GPU
  • The performance impact of different synchronization methods, different numbers of threads, or different algorithms
  • Thread activity and transitions
  • Hardware-related issues in your code such as data sharing, cache misses, branch misprediction, and others
Usage Models
  • Install
    VTune
    Profiler
     on Windows*, macOS*, or Linux* platforms and use it to analyze local and remote target systems.
    • On a macOS system, you can install
      VTune
      Profiler
       and run a remote analysis and view collected data on the macOS host. You cannot profile the local macOS system. On all supported systems,
  • On all supported platforms, use the GUI or run analyses from the command line interface (
    vtune
    ) to collect data and perform regression testing.
  • Use
    VTune
    Profiler
     as a web server. This is an optimal solution for multi-user environments.
  • Install the standalone GUI client or integrate
    VTune
    Profiler
     into IDEs, such as Microsoft Visual Studio* or Eclipse*.
Documentation for versions of Intel® VTune™ Profiler prior to the 2021 release are available for download only. For a list of available documentation downloads by product version, see these pages:

Key Features

This table summarizes the availability of important analysis types per host and remote target platform using
VTune
Profiler
:
Analysis
Windows Target
Linux Target
Android Target
FreeBSD* Target
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
I/O analysis (including DPDK and SPDK apps)
+
+
+
+
+
+
+
+²
+
+¹
+¹
+
+²
+²
+
+
+
+
+
+
+³
+³
+
+
+
+
+
+
+
+
Energy analysis (visualization only)
+
+
+
¹Preview only; ²Intel HD Graphics and Intel Iris® Graphics only; ³EBS analysis only
VTune
Profiler
 provides features that facilitate the analysis and interpretation of the results:
  • Top-down tree analysis: Use to understand which execution flow in your application is more performance-critical.
  • Timeline analysis: Analyze thread activity and the transitions between threads.
  • ITT API analysis: Use the ITT API to mark significant transition points in your code and analyze performance per frame, task, and so on.
  • Architecture diagram: Analyze GPU OpenCL™ applications by exploring the GPU hardware metrics per GPU architecture blocks.
  • Source analysis: View source with performance data attributed per source line to explore possible causes of an issue.
  • Comparison analysis: Compare performance analysis results for several application runs to localize the performance changes you got after optimization.
  • Start data collection paused mode: Click the
    Start Paused
     button on the command bar to start the application without collecting performance data and click the
    Resume
     button to enable the collection at the right moment.
  • Grouping: Group your data by different granularity in the grid view to analyze the problem from different angles.
  • Viewpoints: Choose among preset configurations of windows and panes available for the analysis result. This helps focus on particular performance problems.
  • Hot keys to start and stop the analysis: Use a batch file to create hot keys to start and stop a particular analysis.
Because
VTune
Profiler
 requires specific knowledge of assembly-level instructions, its analysis may not operate correctly if a program (target) is compiled to generate non-Intel architecture instructions. In this case, run the analysis with a target executable compiled to generate only Intel instructions. After you finish using
VTune
Profiler
, you can use optimizing compiler options that generate non-Intel architecture instructions.

Product and Performance Information

1

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