Facebook use bittorrent as part of their deployment process, they exploit rack and cluster affinity to improve performance [1].<p>[1] <a href="https:&#x2F;&#x2F;facebook.com&#x2F;&#x2F;download&#x2F;1411324735760067&#x2F;devops.pdf" rel="nofollow">https:&#x2F;&#x2F;facebook.com&#x2F;&#x2F;download&#x2F;1411324735760067&#x2F;devops.pdf</a>