Linux is a modular operating system, meaning that there are relatively few interrelationships between any two parts of the program code. Access to Linux’s kernel potentially increases both flexibility and configurability. The reality is that the trade-off for this flexibility tends to be increased complexity. For example, in an enterprise server environment, each Linux administrator can add functionality, implement patches, or manage security in different ways. This greater variability in management has significant cost and risk implications in the real world where workloads span hundreds or thousands of servers. Furthermore, distributor-imposed limitations on what, if any, components of the kernel and packages can be modified means that administrators can quickly find themselves outside of supported configurations.
To assess how underlying platform differences in Linux and Windows play out in real-world environments, Security Innovations, a security and reliability consulting firm, simulated the evolution of an e-commerce company through changing business requirements while continuing to maintain security through patch application. Over this virtual year of proactive security management, monthly patch management and functional updates, Security Innovations found that the Windows platform was more reliable than Linux as business needs changed. Specifically, Linux administrators, on average, required 69% more time to maintain the system while adding new capabilities and performing version updates than Windows administrators.
In similar research, VeriTest found that Red Hat Linux end users experienced 15% more service loss than Windows end users and that Windows is 37% faster to update and reconfigure than Linux. Echoing 3rd party research findings, customers have completed their own workload-specific evaluations, such as Michael Chadwick, Vice President of Technology at GoDaddy.com, the world’s largest domain registrar, who offers "We expected a big disparity between performance on Windows and Linux. That’s the myth: that Linux and Apache are the better Web service platform. But we debunked the myth."