Windows 10 Was Done Last Month; Linux Yesterday
We only found out about the SWAPGS variant of Spectre V1 which affects Intel processors yesterday, but apparently Microsoft quietly pushed a Windows 10 patch for it last month. The reason for the delay was that there was no mitigation for Linux machines until yesterday, but now it is here and of course Phoronix has already tested its impact on performance. You are unlikely to be spied upon with this vulnerability as there are much easier ways to infect your machine and connection.
Check out more information, as well as appreciate the creator of the art work above over at Lansweeper.
As to the performance, thankfully it has a minimal effect on your performance.