I have two servers, both have Intel 8160 processor, 768 GB memory, same hardware specs, same software/package versions. The only difference being that one is running RedHat Enterprise Linux 7 and the other one is running Oracle Enterprise Linux 7. For every test, the phoronix benchmarks for the server running OEL are way lower than the server running RHEL, In fact, they are not even comparable to the server running RHEL. Plus, I tested both OSes before and after patching against spectre/meltdown vulnerabilities, but still results for RHEL are much superior in every way. Whats even more surprising is that the server running RHEL has CPU frequency scaling enabled, but the one running OEL has all CPUs running at full speed. Can all this be attributed to the difference between OEL and RHEL kernel? Though OEL/RHEL share the same source, I'm at a loss to understand what can cause such huge performance degradation between two machines having same hardware specs?