While every few weeks or so we have ended up running benchmarks of the latest Linux Git kernel to see the evolving performance impact of KPTI (Kernel Page Table Isolation) and Retpolines for Meltdown and Spectre V2 mitigation, respectively, a request came in last week from a premium supporter to see some new comparison test runs on CentOS 7 with its older 3.10-evolved kernel.

For satisfying that reader request, on the two current highest-end Intel/AMD server platforms I have available for testing (the dual Xeon Gold 6138 and EPYC 7601, both platforms kindly provided by Tyan) I ran some benchmarks using all of the latest CentOS 7 stable updates. On each system in the updated state I compared the stock/out-of-the-box performance with Spectre V2 mitigation as well as PTI (enabled on the Intel system) and then with both Spectre V2 / Meltdown mitigation techniques disabled.