Why it matters: Spectre and Meltdown were seriously dangerous security flaws and companies rushed to secure their devices. Because most of the protections were quick patches rather than well-thought-out security systems, performance suffered as a result.
Gaming performance on Intel processors dropped by 3-4% on average, 5% at most. But SSD storage suffered the most, where people were complaining of up to 30% decreases in speed. Fortunately, by enabling the Retpoline mitigation strategy with the Windows 10 19H1 update coming early next year, performance will be uplifted to only ~1-2% below to where it was originally.
Alex Ionescu noticed that his Surface Pro 4 running the Windows 19H1 beta had much faster storage speeds, and asked a Windows Kernel developer if they'd managed to lessen the performance impact of the patch.
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.— Mehmet Iyigun (@mamyun) October 18, 2018
This is good news, especially for Intel-based systems that were the most affected but it seems that Microsoft won’t be backporting the update (adding it to previous Windows 10 builds). Many companies that prefer to stay on older but more stable versions of Windows won’t be happy that they need to update to see the uplift, though for good reason considering the last major Windows update did come with glaring issues.