Setup CNTK with script on Windows
If you want to build CNTK from source code and want to use the Developer Install script, this page is for you.
If you are looking for any other kind of support in setting up a CNTK build environment or installing CNTK on your system, you should go here instead.
Here are recommendations to make sure you can build CNTK successfully:
- The system locale on the build machine should be set to a language with a 'latin' based character set.
- Avoid extremely long path names. The build procedure uses copy-operations (XCOPY) that can run into problems with path expression with over 256 characters in length.
CNTK requires a 64-bit Windows installation. We tested the build process on Windows 8.1, Windows 10, and Windows Server 2012 R2 and later. Other environments are not officially supported. For compatibility issues check CNTK Production Build and Test configuration.
There are steps required to create a CNTK development environment on your machine:
- Installation of required tools
- Visual Studio 2015 Update 3
- NVIDIA CUDA 8
- Git
- Clone the CNTK Source code
- Running the developer installation script
- Build and test
This page will walk you through all these steps. The script driven installation will create a development environment with all optional components, including NVIDIA tools, the Python environment, OpenCV and compression libraries.
Install Microsoft Visual Studio 2015.3 for Windows. A link to the download can be found here. Please install Visual Studio 2015, not a previous version or the 2017-Preview! The Community Version of Visual Studio 2015 is sufficient to build CNTK.
During the installation process please select custom installation:
On the feature selection screen make sure you add 'Common Tools for Visual C++ 2015' to your installation:
If you already have VS 2015 installed, make sure you are on Update 3. See the Help->About menu to display the version number like "Version 14.0.25431.01 Update 3".
You are also required to have the 'Common Tools for Visual C++ 2015' installed on your system. To check open the Windows "Control Panel -> Programs -> Programs and Features' and select 'Microsoft Visual Studio Enterprise 2015 with Updates' from the list of installed programs. This will start the Visual Studio setup again and allows you to make sure the 'Common Tools for Visual C++ 2015' feature is installed on your system (see picture above).
Important In case you have a first-time Visual Studio 2015 installation as described above, you will need to install NVIDIA CUDA 8 now, even if you have already an existing installation of CUDA 8! The NVIDIA CUDA 8 installation adds support to the NVIDIA development tools to the Visual Studio environment, which is required to build CNTK successfully.
CNTK is set to build with CUDA 8.0. Download and install the NVIDIA CUDA 8.0 Toolkit:
- Download the required package from this download page
- Run the installation procedure (Choose the 'Express Install Option' if the choice is presented)
Note: In case you don't have a system with a NVIDIA CUDA 8 compatible graphics card, the CUDA installer will issue a warning. Please continue the installer if you receive this warning, the CUDA tools will be installed, and you are able to build a NVIDIA Gpu enabled version of CNTK on your system.
Git is required to clone the CNTK code base. There are various Git client tools available. You can also work with Git directly from inside Visual Studio. Here we assume you installed Git for Windows. We assume you installed Git using the default options in the Git installer (Especially 'Use Git from the Windows Command Prompt' and with the option "Checkout Windows-style, commit UNIX-style line endings" at the "Configuring line endings" prompt enabled.
We will create a clone of the CNTK source code in the c:\repos\cntk. If you prefer a different location you will need to adjust the commands accordingly.
Open a standard windows command shell, and execute these command
c: && md \repos && cd \repos
git clone https://github.com/Microsoft/cntk
cd cntk
git submodule update --init -- Source/Multiverso
The submodule Multiverso is used to enable DataParallelASGD for training. If you don't need DataParallelASGD support, then add the environment variable CNTK_ENABLE_ASGD and set its value to false. E.g. run this in an CMD prompt, and then reopen your CMD shell(s) and Visual Studio to pick up the change:
setx CNTK_ENABLE_ASGD false
IMPORTANT! The procedure above does not provide you with the access to 1-bit Stochastic Gradient Descent (1bit-SGD) and BlockMomentumSGD components. If you want to build CNTK with this functionality enabled, please read the instructions on this page and then proceed with the installation.
The developer installation script (devInstall.ps1) is a Powershell script located in the tools subdirectory inside the root of the CNTK repository. It will install all required and optional tools to build CNTK on your system. It will also create the required user-local environment settings. Once the script is started no additional user input is necessary, although you will require to acknowledge the installation of programs or creation of environment variables, depending on your 'User Account Control' setting.
By default no additional options are required to run the installation script (we describe the -Execute option later on this page). There are various additional options to adapt the script functions to your requirements. More details are here.
By default Powershell doesn't allow the execution of any scripts. To allow execution of the installation script from a standard Windows command shell start Powershell by:
start powershell -executionpolicy remotesigned
Assuming that you cloned the CNTK source code into the c:\repos\cntk directory, change inside the Powershell session into the directory with the install script inside the cloned CNTK repository and start the installer in that directory:
cd C:\repos\cntk\Tools\devInstall\Windows
.\DevInstall.ps1
The script will inspect your system and determine the pre-requisites which are missing. You will be notified about the proposed installation steps. At this point you are running in a demo mode - NO changes to your system are being performed.
If you are satisfied with the proposed changes, you can proceed to the actual installation. The installation script supports several command line options. get-help .\install.ps1 will give you a list over the available option. At this point it is recommended to start the installation by adding the -Execute parameter:
.\devInstall.ps1 -execute
The script will download needed components from the web, therefore a connection to the Internet is required. It will execute these components, and according to the setting of UAC (User Account Control) on your system, you will be asked to acknowledge the execution and installation of these components.
Depending on the speed of your system and your Internet connection, the whole process can take between 20 and 30 minutes. Especially the Anaconda3 install is very time consuming without any progress indication, please be patient. The downloaded files from the internet are being cache in the directory [c:\installCacheCntk] and allows you to rerun the installer without going through the component download again. In case of any problems you can restart the installer again, it will not reinstall already successfully installed components. Note: If the installer is interrupted you might need to restart PowerShell in order to propagate the new environment variables.
At this point all the required components to build CNTK on you system are installed. You can follow the steps found here to build and test CNTK.
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