Linux continues to be the number one choice of world's top supercomputers
In Top 500 supercomputer list was compiled in June 1993, Linux was already the top choice of the world's top 500 supercomputers with almost running on 476 out of the top 500 fastest supercomputers in the world. But when 2014 Top 500 supercomputer list is published, it looks like that Linux is completely driving its competitors out of the competition. Linux sets a new high with 485 supercomputers out of the top 500 running Linux in the world now. In other words 97 percent of the fastest computers in the world are based on Linux.
First Unix ruled the supercomputer untill 1999 and now Linux for the last few years has ruled supercomputers. When the first Top 500 supercomputer list was compiled in June 1993, Linux was just getting momentum. But now after 21 years, as reported in The Linux Foundation's report that, "after first appearing on the list in 1998, Linux has consistently dominated the top 10 over the past decade and has comprised more than 90 percent of the list since June 2010."
This success of Linux is driven by two main factors. First, is that with lots of most of the supercomputers in the world are used for conducting high-performance research. Thus, Linux is the number one choice since its open source and research teams can easily modify and optimize its kernel according to their requirements. The scientists have the full leverage to use it for whatever purpose they want.
The second important factor is the cost. No matter how many Linux nodes you are using. It doesn't cost a single penny for your operating system. All you have to do is to bear cost of the hardware resources. Linux support is also very cheap and developer resources are easily available to help with very low costs as compared to other operating systems.
The result seems to be very promising for Linux in near future. At least the current decade till 2020, all belongs to Linux as a first choice supercomputer operating system.