
Building MXNet with [Intel MKL-DNN](https://github.com/intel/mkl-dnn) will gain better performance when using Intel Xeon CPUs for training and inference. The improvement of performance can be seen in this [page](https://mxnet.incubator.apache.org/faq/perf.html#intel-cpu). Below are instructions for linux, MacOS and Windows platform.

<h2 id="0">Contents</h2>

* [1. Linux](#1)
* [2. MacOS](#2)
* [3. Windows](#3)
* [4. Verify MXNet with python](#4)
* [5. Enable MKL BLAS](#5)
* [6. Support](#6)

<h2 id="1">Linux</h2>

### Prerequisites

```
sudo apt-get update
sudo apt-get install -y build-essential git
sudo apt-get install -y libopenblas-dev liblapack-dev
sudo apt-get install -y libopencv-dev
sudo apt-get install -y graphviz
```

### Clone MXNet sources

```
git clone --recursive https://github.com/apache/incubator-mxnet.git
cd incubator-mxnet
```

### Build MXNet with MKL-DNN

```
make -j $(nproc) USE_OPENCV=1 USE_MKLDNN=1 USE_BLAS=mkl USE_INTEL_PATH=/opt/intel
```

If you don't have full [MKL](https://software.intel.com/en-us/intel-mkl) library installed, you can use OpenBLAS by setting `USE_BLAS=openblas`.

<h2 id="2">MacOS</h2>

### Prerequisites

Install the dependencies, required for MXNet, with the following commands:

- [Homebrew](https://brew.sh/)
- gcc (clang in macOS does not support OpenMP)
- OpenCV (for computer vision operations)

```
# Paste this command in Mac terminal to install Homebrew
/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

# install dependency
brew update
brew install pkg-config
brew install graphviz
brew tap homebrew/core
brew install opencv
brew tap homebrew/versions
brew install gcc49
brew link gcc49 #gcc-5 and gcc-7 also work
```

### Clone MXNet sources

```
git clone --recursive https://github.com/apache/incubator-mxnet.git
cd incubator-mxnet
```

### Enable OpenMP for MacOS

If you want to enable OpenMP for better performance, you should modify the Makefile in MXNet root dictionary:

Add CFLAGS '-fopenmp' for Darwin.

```
ifeq ($(USE_OPENMP), 1)
# ifneq ($(UNAME_S), Darwin)
    CFLAGS += -fopenmp
# endif
endif
```

### Build MXNet with MKL-DNN

```
make -j $(sysctl -n hw.ncpu) CC=gcc-4.9 CXX=g++-4.9 USE_OPENCV=0 USE_OPENMP=1 USE_MKLDNN=1 USE_BLAS=apple USE_PROFILER=1
```

*Note: Temporarily disable OPENCV.*

<h2 id="3">Windows</h2>

We recommend to build and install MXNet yourself using [Microsoft Visual Studio 2015](https://www.visualstudio.com/vs/older-downloads/), or you can also try experimentally the latest [Microsoft Visual Studio 2017](https://www.visualstudio.com/downloads/).

**Visual Studio 2015**

To build and install MXNet yourself, you need the following dependencies. Install the required dependencies:

1. If [Microsoft Visual Studio 2015](https://www.visualstudio.com/vs/older-downloads/) is not already installed, download and install it. You can download and install the free community edition.
2. Download and Install [CMake 3](https://cmake.org/) if it is not already installed.
3. Download and install [OpenCV 3](http://sourceforge.net/projects/opencvlibrary/files/opencv-win/3.0.0/opencv-3.0.0.exe/download).
4. Unzip the OpenCV package.
5. Set the environment variable ```OpenCV_DIR``` to point to the ```OpenCV build directory``` (```C:\opencv\build\x64\vc14``` for example). Also, you need to add the OpenCV bin directory (```C:\opencv\build\x64\vc14\bin``` for example) to the ``PATH`` variable.
6. If you have Intel Math Kernel Library (MKL) installed, set ```MKL_ROOT``` to point to ```MKL``` directory that contains the ```include``` and ```lib```. If you want to use MKL blas, you should set ```-DUSE_BLAS=mkl``` when cmake. Typically, you can find the directory in
```C:\Program Files (x86)\IntelSWTools\compilers_and_libraries_2018\windows\mkl```.
7. If you don't have the Intel Math Kernel Library (MKL) installed, download and install [OpenBLAS](http://sourceforge.net/projects/openblas/files/v0.2.14/). Note that you should also download ```mingw64.dll.zip`` along with openBLAS and add them to PATH.
8. Set the environment variable ```OpenBLAS_HOME``` to point to the ```OpenBLAS``` directory that contains the ```include``` and ```lib``` directories. Typically, you can find the directory in ```C:\Program files (x86)\OpenBLAS\```. 

After you have installed all of the required dependencies, build the MXNet source code:

1. Download the MXNet source code from [GitHub](https://github.com/apache/incubator-mxnet). Don't forget to pull the submodules:
```
git clone --recursive https://github.com/apache/incubator-mxnet.git
```

2. Copy file `3rdparty/mkldnn/config_template.vcxproj` to incubator-mxnet root.

3. Start a Visual Studio command prompt.

4. Use [CMake 3](https://cmake.org/) to create a Visual Studio solution in ```./build``` or some other directory. Make sure to specify the architecture in the 
[CMake 3](https://cmake.org/) command:
```
mkdir build
cd build
cmake -G "Visual Studio 14 Win64" .. -DUSE_CUDA=0 -DUSE_CUDNN=0 -DUSE_NVRTC=0 -DUSE_OPENCV=1 -DUSE_OPENMP=1 -DUSE_PROFILER=1 -DUSE_BLAS=open -DUSE_LAPACK=1 -DUSE_DIST_KVSTORE=0 -DCUDA_ARCH_NAME=All -DUSE_MKLDNN=1 -DCMAKE_BUILD_TYPE=Release
```

5. In Visual Studio, open the solution file,```.sln```, and compile it.
These commands produce a library called ```libmxnet.dll``` in the ```./build/Release/``` or ```./build/Debug``` folder.
Also ```libmkldnn.dll``` with be in the ```./build/3rdparty/mkldnn/src/Release/```

6. Make sure that all the dll files used above(such as `libmkldnn.dll`, `libmklml.dll`, `libiomp5.dll`, `libopenblas.dll`, etc) are added to the system PATH. For convinence, you can put all of them to ```\windows\system32```. Or you will come across `Not Found Dependencies` when loading mxnet.

**Visual Studio 2017**

To build and install MXNet yourself using [Microsoft Visual Studio 2017](https://www.visualstudio.com/downloads/), you need the following dependencies. Install the required dependencies:

1. If [Microsoft Visual Studio 2017](https://www.visualstudio.com/downloads/) is not already installed, download and install it. You can download and install the free community edition.
2. Download and install [CMake 3](https://cmake.org/files/v3.11/cmake-3.11.0-rc4-win64-x64.msi) if it is not already installed.
3. Download and install [OpenCV](https://sourceforge.net/projects/opencvlibrary/files/opencv-win/3.4.1/opencv-3.4.1-vc14_vc15.exe/download).
4. Unzip the OpenCV package.
5. Set the environment variable ```OpenCV_DIR``` to point to the ```OpenCV build directory``` (e.g., ```OpenCV_DIR = C:\utils\opencv\build```).
6. If you don't have the Intel Math Kernel Library (MKL) installed, download and install [OpenBlas](https://sourceforge.net/projects/openblas/files/v0.2.20/OpenBLAS%200.2.20%20version.zip/download).
7. Set the environment variable ```OpenBLAS_HOME``` to point to the ```OpenBLAS``` directory that contains the ```include``` and ```lib``` directories (e.g., ```OpenBLAS_HOME = C:\utils\OpenBLAS```).

After you have installed all of the required dependencies, build the MXNet source code:

1. Start ```cmd``` in windows.

2. Download the MXNet source code from GitHub by using following command:

```r
cd C:\
git clone --recursive https://github.com/apache/incubator-mxnet.git
```

3. Copy file `3rdparty/mkldnn/config_template.vcxproj` to incubator-mxnet root.

4. Follow [this link](https://docs.microsoft.com/en-us/visualstudio/install/modify-visual-studio) to modify ```Individual components```, and check ```VC++ 2017 version 15.4 v14.11 toolset```, and click ```Modify```.

5. Change the version of the Visual studio 2017 to v14.11 using the following command (by default the VS2017 is installed in the following path):

```r
"C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Auxiliary\Build\vcvars64.bat" -vcvars_ver=14.11
```

6. Create a build dir using the following command and go to the directory, for example:

```r
mkdir C:\build
cd C:\build
```

7. CMake the MXNet source code by using following command:

```r
cmake -G "Visual Studio 15 2017 Win64" .. -T host=x64 -DUSE_CUDA=0 -DUSE_CUDNN=0 -DUSE_NVRTC=0 -DUSE_OPENCV=1 -DUSE_OPENMP=1 -DUSE_PROFILER=1 -DUSE_BLAS=open -DUSE_LAPACK=1 -DUSE_DIST_KVSTORE=0 -DCUDA_ARCH_NAME=All -DUSE_MKLDNN=1 -DCMAKE_BUILD_TYPE=Release
```

8. After the CMake successfully completed, compile the the MXNet source code by using following command:

```r
msbuild mxnet.sln /p:Configuration=Release;Platform=x64 /maxcpucount
```

9. Make sure that all the dll files used above(such as `libmkldnn.dll`, `libmklml.dll`, `libiomp5.dll`, `libopenblas.dll`, etc) are added to the system PATH. For convinence, you can put all of them to ```\windows\system32```. Or you will come across `Not Found Dependencies` when loading mxnet.

<h2 id="4">Verify MXNet with python</h2>

```
cd python
sudo python setup.py install
python -c "import mxnet as mx;print((mx.nd.ones((2, 3))*2).asnumpy());"

Expected Output:

[[ 2.  2.  2.]
 [ 2.  2.  2.]]
```

### Verify whether MKL-DNN works

After MXNet is installed, you can verify if MKL-DNN backend works well with a single Convolution layer.

```
import mxnet as mx
import numpy as np

num_filter = 32
kernel = (3, 3)
pad = (1, 1)
shape = (32, 32, 256, 256)

x = mx.sym.Variable('x')
w = mx.sym.Variable('w')
y = mx.sym.Convolution(data=x, weight=w, num_filter=num_filter, kernel=kernel, no_bias=True, pad=pad)
exe = y.simple_bind(mx.cpu(), x=shape)

exe.arg_arrays[0][:] = np.random.normal(size=exe.arg_arrays[0].shape)
exe.arg_arrays[1][:] = np.random.normal(size=exe.arg_arrays[1].shape)

exe.forward(is_train=False)
o = exe.outputs[0]
t = o.asnumpy()
```

You can open the `MKLDNN_VERBOSE` flag by setting environment variable:
```
export MKLDNN_VERBOSE=1
```
Then by running above code snippet, you probably will get the following output message which means `convolution` and `reorder` primitive from MKL-DNN are called. Layout information and primitive execution performance are also demonstrated in the log message.
```
mkldnn_verbose,exec,reorder,jit:uni,undef,in:f32_nchw out:f32_nChw16c,num:1,32x32x256x256,6.47681
mkldnn_verbose,exec,reorder,jit:uni,undef,in:f32_oihw out:f32_OIhw16i16o,num:1,32x32x3x3,0.0429688
mkldnn_verbose,exec,convolution,jit:avx512_common,forward_inference,fsrc:nChw16c fwei:OIhw16i16o fbia:undef fdst:nChw16c,alg:convolution_direct,mb32_g1ic32oc32_ih256oh256kh3sh1dh0ph1_iw256ow256kw3sw1dw0pw1,9.98193
mkldnn_verbose,exec,reorder,jit:uni,undef,in:f32_oihw out:f32_OIhw16i16o,num:1,32x32x3x3,0.0510254
mkldnn_verbose,exec,reorder,jit:uni,undef,in:f32_nChw16c out:f32_nchw,num:1,32x32x256x256,20.4819
```

<h2 id="5">Enable MKL BLAS</h2>

To make it convenient for customers, Intel introduced a new license called [Intel® Simplified license](https://software.intel.com/en-us/license/intel-simplified-software-license) that allows to redistribute not only dynamic libraries but also headers, examples and static libraries.

Installing and enabling the full MKL installation enables MKL support for all operators under the linalg namespace.

  1. Download and install the latest full MKL version following instructions on the [intel website.](https://software.intel.com/en-us/mkl)

  2. Run `make -j ${nproc} USE_BLAS=mkl`

  3. Navigate into the python directory

  4. Run `sudo python setup.py install`

### Verify whether MKL works

After MXNet is installed, you can verify if MKL BLAS works well with a single dot layer.

```
import mxnet as mx
import numpy as np

shape_x = (1, 10, 8)
shape_w = (1, 12, 8)

x_npy = np.random.normal(0, 1, shape_x)
w_npy = np.random.normal(0, 1, shape_w)

x = mx.sym.Variable('x')
w = mx.sym.Variable('w')
y = mx.sym.batch_dot(x, w, transpose_b=True)
exe = y.simple_bind(mx.cpu(), x=x_npy.shape, w=w_npy.shape)

exe.forward(is_train=False)
o = exe.outputs[0]
t = o.asnumpy()
```

You can open the `MKL_VERBOSE` flag by setting environment variable:
```
export MKL_VERBOSE=1
```
Then by running above code snippet, you probably will get the following output message which means `SGEMM` primitive from MKL are called. Layout information and primitive execution performance are also demonstrated in the log message.
```
Numpy + Intel(R) MKL: THREADING LAYER: (null)
Numpy + Intel(R) MKL: setting Intel(R) MKL to use INTEL OpenMP runtime
Numpy + Intel(R) MKL: preloading libiomp5.so runtime
MKL_VERBOSE Intel(R) MKL 2018.0 Update 1 Product build 20171007 for Intel(R) 64 architecture Intel(R) Advanced Vector Extensions 512 (Intel(R) AVX-512) enabled processors, Lnx 2.40GHz lp64 intel_thread NMICDev:0
MKL_VERBOSE SGEMM(T,N,12,10,8,0x7f7f927b1378,0x1bc2140,8,0x1ba8040,8,0x7f7f927b1380,0x7f7f7400a280,12) 8.93ms CNR:OFF Dyn:1 FastMM:1 TID:0  NThr:40 WDiv:HOST:+0.000
```

<h2 id="6">Next Steps and Support</h2>

- For questions or support specific to MKL, visit the [Intel MKL](https://software.intel.com/en-us/mkl)

- For questions or support specific to MKL, visit the [Intel MKLDNN](https://github.com/intel/mkl-dnn)

- If you find bugs, please open an issue on GitHub for [MXNet with MKL](https://github.com/apache/incubator-mxnet/labels/MKL) or [MXNet with MKLDNN](https://github.com/apache/incubator-mxnet/labels/MKLDNN)
