Like the fixes introduced by other companies, the security patches Microsoft introduced to combat the Spectre and Meltdown vulnerabilities had a negative performance impact on certain systems.
Windows Kernel team development manager Mehmet Iyigun has now stated on Twitter that the company will reduce the performance hit of these patches in a future update to Windows 10.
Iyigun said the patch will reduce the performance impact of Spectre v2 mitigations to “noise-level” for most scenarios.
The update will be rolled out to users in the first half of 2019 and will use Google’s Retpoline solution to protect against Spectre attacks, while maintaining performance.
Retpoline addresses the second variant of Spectre, which leverages CPU speculative execution to access sensitive data.
“Retpoline” is a portmanteau of “return” and “trampoline”, and refers to a software construct that allows indirect branches of a program to be isolated from speculative execution.
Yes, we have enabled retpoline by default in our 19H1 flights along with what we call "import optimization" to further reduce perf impact due to indirect calls in kernel-mode. Combined, these reduce the perf impact of Spectre v2 mitigations to noise-level for most scenarios. https://t.co/CPlYeryV9K
— Mehmet Iyigun (@mamyun) October 18, 2018