Initial Benchmarks Of The Spectre "SWAPGS" Mitigation Performance Impact

In the other common benchmarks tested, the SWAPGS performance impact tended to be 1% or less at least for this latest generation Intel Core i9 9900K desktop. Additional tests are currently being conducted on more hardware and more benchmarks. At least as it stands now it seems to be largely a 1% or less performance hit (with select exceptions at ~5%), so not nearly as bad as the other Spectre/Meltdown/Foreshadow/Zombieload mitigations, but this is on top of all that we've seen since January 2018.