Sadly, Linux has become old, fat, and slow. After two decades of overindulgence, the once-lean OS has gained some ugly pounds of cruft.
Linux may not be the most overweight server OS out there, but it does take up more resources than it used to. According to the Linux Foundation's 2014 Enterprise End User Report, 75% of enterprise cloud platforms are Linux. Since millions of cloud computing services are powered by Linux, that's a lot of extra resources consumed.