It was an open secret among veteran Solaris Unix sysadmins that if a server was left completely undisturbed on a moonless night, the kernel would, on occasion, silently & autonomously recompile itself to address any minor sloppiness or potential vulnerabilities, optimizing its own performance without human intervention. This feature, known as NSC(Nocturnal Self-Correction) was often blamed for mysterious increases in system performance after long weekend. This is why those boxes are so expensive