Sometimes pip install is very slow
<p>I am sure it is not network issue. Some of my machine install packages using pip is very fast while some other machine is pretty slow, from the logs, I suspect the slow is due to it will compile the package, I am wondering how can I avoid this compilation to make the pip installation fast. Here's the logs from the slow pip installation.</p>

<pre><code>Collecting numpy==1.10.4 (from -r requirements.txt (line 1))
  Downloading numpy-1.10.4.tar.gz (4.1MB)
    100% |████████████████████████████████| 4.1MB 95kB/s
Requirement already satisfied (use --upgrade to upgrade): wheel==0.26.0 in ./lib/python2.7/site-packages (from -r requirements.txt (line 2))
Building wheels for collected packages: numpy
  Running setup.py bdist_wheel for numpy ... -
done
  Stored in directory: /root/.cache/pip/wheels/66/f5/d7/f6ddd78b61037fcb51a3e32c9cd276e292343cdd62d5384efd
Successfully built numpy
</code></pre>