Benchmarks Of Intel's Latest Linux Microcode Update

The Hackbench Linux kernel benchmark did see slightly lower performance with the newest Intel CPU microcode, but it wasn't any huge difference -- and less than the L1TF patches itself.

In the benchmarks run over the weekend, the latest Intel microcode files for August (taking Xeon Scalable CPUs to 0x200004d appeared to have only minimal impact on the system performance... Mostly in I/O cases were there some slight differences in performance, but nothing overly shocking and not as bad as the L1TF Linux kernel mitigation itself -- see those benchmarks for all the details. Going into this microcode comparison I was expecting much more volatile results given their short-lived benchmark restriction, but it looks like it may have just been an overzealous Intel lawyer who thought it would be a good idea to forbid benchmarking and further lock-down their microcode license...