Anandtech published Analyzing Core i9-9900K Performance with Spectre and Meltdown Hardware Mitigations
A quote from the article:
One of the key aspects of the most recent Intel processor launch, its Core 9th Generation processors, is that the new design affords some hardware-based protection for a couple of the Spectre and Meltdown family of security vulnerabilities. When these vulnerabilities were first discovered, they were patched using a combination of software and firmware, which unfortunately led to some performance regressions over an unpatched processor. The ultimate goal is for a hardware patch, which is always enabled, that loses zero performance – we’re testing out what the new patches have for us today.Analyzing Core i9-9900K Performance with Spectre and Meltdown Hardware Mitigations