Ubuntu16.04运行TensorFlow出现SSE3等问题

在使用pip安装的TensorFlow的时候，运行会出现如下警告提醒：

W tensorflow/core/platform/cpu_feature_guard.cc:45] The TensorFlow library wasn't compiled to use SSE4.1 instructions, but these are available on your machine and could speed up CPU computations.
W tensorflow/core/platform/cpu_feature_guard.cc:45] The TensorFlow library wasn't compiled to use SSE4.2 instructions, but these are available on your machine and could speed up CPU computations.
W tensorflow/core/platform/cpu_feature_guard.cc:45] The TensorFlow library wasn't compiled to use AVX instructions, but these are available on your machine and could speed up CPU computations.
W tensorflow/core/platform/cpu_feature_guard.cc:45] The TensorFlow library wasn't compiled to use AVX2 instructions, but these are available on your machine and could speed up CPU computations.
W tensorflow/core/platform/cpu_feature_guard.cc:45] The TensorFlow library wasn't compiled to use FMA instructions, but these are available on your machine and could speed up CPU computations.

为了解决这个问题，我们需要从source安装tensorflow。

首先卸载安装好的TensorFlow

~$ sudo pip uninstall tensorflow

然后clone TensorFlow

~$ git clone --recurse-submodules https://github.com/tensorflow/tensorflow

由于编译TensorFlow的时候要用到Bazel，接下来需要安装Bazel。

~$ sudo apt-get install openjdk-8-jdk
~$ echo "deb [arch=amd64] http://storage.googleapis.com/bazel-apt stable jdk1.8" | sudo tee /etc/apt/sources.list.d/bazel.list
~$ curl https://bazel.build/bazel-release.pub.gpg | sudo apt-key add -
~$ sudo apt-get update 
~$ sudo apt-get install bazel
~$ sudo apt-get upgrade bazel

接着安装依赖

sudo apt-get install python-numpy python-dev python-pip python-wheel

运行tensorflow配置文件(运行命令后会有输出，全部回车即可)

~$ cd tensorflow
~$ ./configure

Build支持CPU的tensorflow的pip package:

~$ bazel build --config=opt //tensorflow/tools/pip_package:build_pip_package

这个运行非常慢，等运行完成之后使用下面命令build一个.whl文件，该文件在/tmp/tensorflow_pkg文件夹中。

~$ bazel-bin/tensorflow/tools/pip_package/build_pip_package /tmp/tensorflow_pkg

最后安装刚刚build好的.whl文件，至此TensorFlow就安装完成了。

~$ sudo pip install /tmp/tensorflow_pkg/tensorflow-1.3.0-cp27-cp27mu-linux_x86_64.whl

验证一下安装是否OK，创建一个ten.py文件:

import tensorflow as tf

hello = tf.constant('hello tensorflow')
sess = tf.Session()
print sess.run(hello)

保存运行

~$ python ten.py

得到结果

hello tensorflow