If you are using older Intel processors or AMD processors, you can boost the performance of Windows 10 by enabling the Retpoline Spectre mitigations that were recently ported to Windows 10 October 2018 Update build 1809.
In order to mitigate the Spectre vulnerabilities
in Windows 10, Microsoft had introduced fixes that caused a performance decrease, which were more noticeable in older CPUs. To resolve these performance issues, Microsoft has been testing a new mitigation technique called Retpoline
in Windows Insider Preview builds since build 18272.
This mitigation has recently been backported
to Windows 10 October 2018 Update build 1809, but is being slowly rolled out over time as they test its performance in large-scale public use. If you do not want to wait, you can use the instructions below to enable it immediately on supported processors.