Intel® VTune™ Profiler Performance Analysis Cookbook

Cookbook

  • 2021
  • 11/09/2021
  • Public Content
Contents

Using
Intel® VTune™
Profiler
 Server with Visual Studio Code and Intel® DevCloud for oneAPI (NEW)

This recipe demonstrates how you use
Intel® VTune™
Profiler
 as a web server when you develop and tune performance on a remote development machine. As an example, we use a compute node at Intel® DevCloud for oneAPI for a remote machine.

Ingredients

Here are the hardware and software tools you need:
  • Starting with the 2020 release, Intel® VTune™ Amplifier has been renamed to
    Intel® VTune™
    Profiler
    .
  • Most recipes in the
    Intel® VTune™
    Profiler
     Performance Analysis Cookbook are flexible. You can apply them to different versions of
    Intel® VTune™
    Profiler
    . In some cases, minor adjustments may be required.
  • Get the latest version of
    Intel® VTune™
    Profiler
    :

Setup Overview

With v2021.1.1 and newer versions, you can run
Intel® VTune™
Profiler
 as a server and access it remotely using a web browser. This setup is useful when you develop applications on a remote system.
  • You can run
    Intel® VTune™
    Profiler
     on the system where you do development, so it has direct access to the binaries, debug info, and source files.
  • Intel® VTune™
    Profiler
     also stores the collected traces and processed data on the same system so you do not have to transfer this heavy data to your client system for analysis.
  • You do not need to install anything on your client system. You only need a web browser to access the
    Intel® VTune™
    Profiler
     GUI.
This figure illustrates the setup for this scenario:
Setup for VTune Profiler Server for Remote Development

Option 1: Use
Intel® VTune™
Profiler
 Server for Remote Development with Visual Studio Code

  2. Set up the VS Code connection. When you complete this procedure, you should get local VS Code connected to a compute node in the DevCloud.
  3. Run
    Intel® VTune™
    Profiler
     server on the compute node from the VS Code terminal: 
    vtune-backend --enable-server-profiling
  4. Run the
    Intel® VTune™
    Profiler
     GUI. Control+click the URL displayed by
    Intel® VTune™
    Profiler
     server in the VS Code terminal to open the
    Intel® VTune™
    Profiler
     GUI in your web browser.

Option 2. Use
Intel® VTune™
Profiler
 Server on a Remote System via SSH Terminal

In this case, you must manually set up SSH tunneling. To simplify this procedure, run VTune on a specific port (
55001
 in this example). You can select a different port if
55001
 is busy.
  2. Follow the instructions for Windows or Linux / MacOS systems and set up an SSH connection into the DevCloud.
  3. Log into the DevCloud login node: 
    ssh devcloud
  4. Reserve a DevCloud compute node: 
    qsub -I
    Do not close the terminal after this step, as the action will release your compute node.
  5. Open a new terminal.
  6. Log into the DevCloud node again, this time with SSH Port forwarding enabled: 
    ssh -L 127.0.0.1:55001:127.0.0.1:55001 devcloud
  7. Establish an SSH connection from the login node to the compute node with one more SSH tunnel: 
    ssh -L 127.0.0.1:55001:127.0.0.1:55001 s000-n000
    Replace
    s000-n000
     with your compute node name.
  8. Start VTune server on the compute node: 
    vtune-backend --web-port=55001 --enable-server-profiling
  9. Open the VTune GUI. Use your web browser to open the URL displayed by the VTune server.

Finish Setup

Whether you chose Option 1 or Option 2, complete the setup by following these steps:
  1. Accept the VTune server certificate.
    When you open the VTune GUI, your web browser may prompt you about the VTune server self-signed certificate. You can proceed safely without installing the certificate because the SSH tunnel provides protection from Man-in-the-Middle (MitM) attacks. For more information on transport security, see Set Up Transport Security.
  2. Set the passphrase.
    When you run VTune server for the first time, the URL that it displays should contain a one-time-token. When you open this URL on a browser,
    Intel® VTune™
    Profiler
     server prompts you to set a passphrase. Other users cannot access your
    Intel® VTune™
    Profiler
     server without the passphrase. The hash of the passphrase is persisted on the server. Also, your browser stores a secure HTTP cookie so that you do not need to enter the passphrase each time you open the VTune GUI. Once you set the passphrase, the
    Intel® VTune™
    Profiler
     welcome screen opens.
  3. Create a project.
  4. Configure an analysis. Your remote machine (running the
    Intel® VTune™
    Profiler
     server) is selected as the target system by default since you ran the server with
    --enable-server-profiling
     option.
  5. Set the target application path and any command-line arguments. For more information, see Set Up Analysis Target.
  6. Run the analysis.

Usage Considerations

  • The setup described in Option 1 relies on the functionality of the VS Code Remote - SSH extension to watch port numbers used by processes that are started through the VS Code terminal. The Remote - SSH extension automatically forwards these ports through the SSH tunnel. This action is controlled by the
    remote.autoForwardPorts
     setting, which is enabled by default.
  • You can use the
    --enable-remote-profiling
     command-line option to enable the system that hosts VTune server as the performance profiling target. This option is disabled by default for security because running a VTune analysis involves launching a target application, which is an arbitrary command line. If multiple users have access to a single instance of VTune server, they would get access to execute arbitrary code on behalf of the user account that runs the
    Intel® VTune™
    Profiler
     server. Enable
    --enable-remote-profiling
     only when VTune server is intended for a single user and you do not share the passphrase used to access the server.
  • Use the
    --web-port=PORT
     command-line option to run VTune server on a specific port. Otherwise,
    Intel® VTune™
    Profiler
     will run on any arbitrary port available on the system.
  • VTune server displays this warning in the output: 
    warn: Server access is limited to localhost only. To enable remote access restart with
    --allow-remote-ui.
    Because this procedure uses SSH port forwarding, you do not need to enable
    --allow-remote-ui
    . Incoming connections to the VTune server come from the SSH server and they are localhost connections. If you enable
    --allow-remote-ui
    , VTune server builds a URL with the real network card IP address or FQDN name, which may not be accessible from your client machine.
  • By default, VTune server stores profiling results in your home directory. Use the
    --data-directory
     command-line argument to specify a different data directory. You can also use this argument to open pre-collected
    Intel® VTune™
    Profiler
     results in
    Intel® VTune™
    Profiler
     server.
    Intel® VTune™
    Profiler
     can locate its results in any child folders.

Product and Performance Information

1

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