Úgy tűnik mégis akad teljesítménycsökkenés nélküli megoldás:
https://www.blog.google/topics/google-cloud/protecting-our-google-cloud…
We believe that Retpoline-based protection is the best-performing solution for Variant 2 on current hardware. Retpoline fully protects against Variant 2 without impacting customer performance on all of our platforms. In sharing our research publicly, we hope that this can be universally deployed to improve the cloud experience industry-wide.