added Dockerfile for CPU backend

Summary:
Dockerfiles update:
- added dockerfile with flashligth CPU backend
- switch arrayfire to 3.6.2 version for CUDA and CPU dockerfiles

Reviewed By: jacobkahn

Differential Revision: D13632520

fbshipit-source-id: a77845a6fbe48e7230bcb5622099ddb8a49da97f

Dockerfile-CPU

@@ -0,0 +1,97 @@
+# ==================================================================
+# module list
+# ------------------------------------------------------------------
+# Ubuntu           16.04
+# OpenMPI          latest     (apt)
+# cmake            3.10       (git)
+# MKL              2018.4-057 (apt)
+# arrayfire        3.6.2      (git, CPU backend)
+# MKLDNN           4bdffc2    (git)
+# Gloo             b7e0906    (git)
+# flashlight       master     (git, CPU backend)
+# ==================================================================
+
+FROM ubuntu:16.04
+
+RUN APT_INSTALL="apt-get install -y --no-install-recommends" && \
+    apt-get update && \
+    DEBIAN_FRONTEND=noninteractive $APT_INSTALL \
+        build-essential \
+        ca-certificates \
+        wget \
+        git \
+        vim \
+        emacs \
+        nano \
+        htop \
+        g++ \
+        # for MKL
+        apt-transport-https \
+        # for arrayfire CPU backend
+        # OpenBLAS
+        libopenblas-dev libfftw3-dev liblapacke-dev \
+        # ATLAS
+        libatlas3-base libatlas-dev libfftw3-dev liblapacke-dev \
+        # ssh for OpenMPI
+        openssh-server openssh-client \
+        # OpenMPI
+        libopenmpi-dev libomp-dev && \
+# ==================================================================
+# cmake 3.10 (for MKLDNN)
+# ------------------------------------------------------------------
+    apt-get purge -y cmake && \
+    # for cmake
+    DEBIAN_FRONTEND=noninteractive $APT_INSTALL zlib1g-dev libcurl4-openssl-dev && \
+    cd /tmp && wget https://cmake.org/files/v3.10/cmake-3.10.3.tar.gz  && \
+    tar -xzvf cmake-3.10.3.tar.gz  && cd cmake-3.10.3  && \
+    ./bootstrap --system-curl && \
+    make -j8 &&  make install && cmake --version && \
+# ==================================================================
+# MKL https://software.intel.com/en-us/mkl
+# ------------------------------------------------------------------
+    cd /tmp && wget https://apt.repos.intel.com/intel-gpg-keys/GPG-PUB-KEY-INTEL-SW-PRODUCTS-2019.PUB && \
+    apt-key add GPG-PUB-KEY-INTEL-SW-PRODUCTS-2019.PUB && \
+    wget https://apt.repos.intel.com/setup/intelproducts.list -O /etc/apt/sources.list.d/intelproducts.list && \
+    sh -c 'echo deb https://apt.repos.intel.com/mkl all main > /etc/apt/sources.list.d/intel-mkl.list' && \
+    apt-get update && DEBIAN_FRONTEND=noninteractive $APT_INSTALL intel-mkl-64bit-2018.4-057 && \
+    export MKLROOT=/opt/intel/mkl && \
+# ==================================================================
+# arrayfire with CPU backend https://github.com/arrayfire/arrayfire/wiki/
+# ------------------------------------------------------------------
+    cd /tmp && git clone --recursive https://github.com/arrayfire/arrayfire.git && \
+    cd arrayfire && git checkout v3.6.2  && \
+    mkdir build && cd build && \
+    CXXFLAGS=-DOS_LNX cmake .. -DCMAKE_BUILD_TYPE=Release -DAF_BUILD_CUDA=OFF -DAF_BUILD_OPENCL=OFF -DAF_BUILD_EXAMPLES=OFF && \
+    make -j8 && make install && \
+# ==================================================================
+# MKLDNN https://github.com/intel/mkl-dnn/
+# ------------------------------------------------------------------
+    cd /tmp && git clone https://github.com/intel/mkl-dnn.git && \
+    cd mkl-dnn && git checkout 4bdffc2 && mkdir -p build && cd build && \
+    cmake .. -DMKLDNN_USE_MKL=FULL && \
+    make -j8 && make install && \
+# ==================================================================
+# Gloo https://github.com/facebookincubator/gloo.git
+# ------------------------------------------------------------------
+    cd /tmp && git clone https://github.com/facebookincubator/gloo.git && \
+    cd gloo && git checkout b7e0906 && mkdir build && cd build && \
+    cmake .. -DUSE_MPI=ON && \
+    make -j8 && make install && \
+# ==================================================================
+# config & cleanup
+# ------------------------------------------------------------------
+    ldconfig && \
+    apt-get clean && \
+    apt-get autoremove && \
+    rm -rf /var/lib/apt/lists/* /tmp/* ~/*
+
+RUN mkdir /root/flashlight
+COPY . /root/flashlight
+
+# ==================================================================
+# flashlight with CPU backend
+# ------------------------------------------------------------------
+RUN export MKLROOT=/opt/intel/mkl && \
+    cd /root/flashlight && mkdir -p build && cd build && \
+    cmake .. -DCMAKE_BUILD_TYPE=Release -DFLASHLIGHT_BACKEND=CPU && \
+    make -j8 && make install

Dockerfile-CUDA

@@ -4,8 +4,8 @@
 # Ubuntu           16.04
 # CUDA             9.2
 # CuDNN            7-dev
-# arrayfire        3.6.1    (git, CUDA backend)
-# OpenMPI          4.0.0    (.gz)
+# arrayfire        3.6.2    (git, CUDA backend)
+# OpenMPI          latest   (apt)
 # flashlight       master   (git, CUDA backend)
 # ==================================================================
 
@@ -29,29 +29,22 @@ RUN APT_INSTALL="apt-get install -y --no-install-recommends" && \
         g++ \
         # ssh for OpenMPI
         openssh-server openssh-client \
+        # OpenMPI
+        libopenmpi-dev libomp-dev \
         # nccl: for flashlight
         libnccl2 libnccl-dev && \
 # ==================================================================
 # arrayfire https://github.com/arrayfire/arrayfire/wiki/
 # ------------------------------------------------------------------
     cd /tmp && git clone --recursive https://github.com/arrayfire/arrayfire.git && \
-    cd arrayfire && git checkout b443e14 && \
+    cd arrayfire && git checkout v3.6.2 && \
     mkdir build && cd build && \
-    cmake .. -DCMAKE_BUILD_TYPE=Release -DAF_BUILD_CPU=OFF -DAF_BUILD_OPENCL=OFF -DAF_BUILD_EXAMPLES=OFF && \
+    CXXFLAGS=-DOS_LNX cmake .. -DCMAKE_BUILD_TYPE=Release -DAF_BUILD_CPU=OFF -DAF_BUILD_OPENCL=OFF -DAF_BUILD_EXAMPLES=OFF && \
     make -j8 && \
     make install && \
 # ==================================================================
-# OpenMPI https://www.open-mpi.org/
-# ------------------------------------------------------------------
-    cd /tmp && wget https://download.open-mpi.org/release/open-mpi/v4.0/openmpi-4.0.0.tar.gz && \
-    gunzip -c openmpi-4.0.0.tar.gz | tar xf - && \
-    cd openmpi-4.0.0 && \
-    ./configure --prefix=/usr/local && \
-    make all install && \
-# ==================================================================
 # config & cleanup
 # ------------------------------------------------------------------
-    # at least to link correctly OpenMPI
     ldconfig && \
     apt-get clean && \
     apt-get autoremove && \

docs/source/installation.rst

@@ -110,15 +110,20 @@ Building flashlight on Windows is not supported at this time (coming soon).
 
 Building/Running flashlight with Docker
 ---------------------------------------
-flashlight and its dependencies can also be built with the provided Dockerfile. Only the CUDA backend is supported with Docker at this time.
+flashlight and its dependencies can also be built with the provided Dockerfile.
 
 To build flashlight with Docker:
-- Install `Docker <https://docs.docker.com/engine/installation/>`_  and `nvidia-docker <https://github.com/NVIDIA/nvidia-docker/>`_
+
+- Install `Docker <https://docs.docker.com/engine/installation/>`_
+- For CUDA backend install `nvidia-docker <https://github.com/NVIDIA/nvidia-docker/>`_
 - Run the given Dockerfile in a new container:
 
 .. code-block:: shell
-
+ # for CUDA backend
  sudo docker run --runtime=nvidia --rm -itd --ipc=host --name flashlight flml/flashlight:cuda-latest
+ # for CPU backend
+ sudo docker run --rm -itd --name flashlight flml/flashlight:cpu-latest
+ # go to terminal in the container
  sudo docker exec -it flashlight bash
 
 - to run tests inside a container
@@ -133,7 +138,10 @@ To build flashlight with Docker:
 
  git clone --recursive https://github.com/facebookresearch/flashlight.git
  cd flashlight
+ # for CUDA backend
  sudo docker build -f ./Dockerfile-CUDA -t flashlight .
+ # for CPU backend
+ sudo docker build -f ./Dockerfile-CPU -t flashlight .
 
 Building Your Project with flashlight
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~