We assume you’re fully aware of Meltdown and Spectre, the two new, and rather scary, CPU exploits, by now. If not, then read our overview of Meltdown and Spectre before continuing. Done? Good. Now it’s time to find out exactly how the Windows updates Microsoft has released will affect your PC.
We have written a whole article answering the question, “Is your Windows PC affected by Meltdown and Spectre?” And now, thanks to Microsoft, we know how the firmware updates designed to fix these CPU exploits will affect your computer. And it’s fair to say there’s some good news and bad news.
Microsoft Reveals Potential Performance Impacts
In a blog post titled, “Understanding the performance impact of Spectre and Meltdown mitigations on Windows Systems,” Terry Myerson, Executive Vice President of the Windows and Devices Group, shares what Microsoft has learned so far about the impact its updates will have on performance.
Essentially, if you’re using an older computer (2015 or earlier) running Windows 7 or Windows 8then you may notice the change in performance. However, if you’re using a newer computer (2016 and later) running Windows 10 then you probably won’t notice the miniscule change in performance.
Diving deeper, Windows 10 PCs with Skylake, Kaby Lake, or newer processors show “single-digit slowdowns […] reflected in milliseconds.” Older Windows 10 PCs with Haswell or older processors may be affected more, but older PCs running Windows 7 or Windows 8 will be the worst hit.
Windows 10 machines running older processors like Haswell “show more significant slowdowns, and we expect that some users will notice a decrease in system performance,” says Myerson. The same older Haswell machines running Windows 7 or Windows 8 will also experience slowdowns that Myerson says “most users” will notice.
Windows 7 and Windows 8 will be the worst hit simply because these older operating systems have features like kernel-level font rendering that will be impacted by the Spectre and Meltdown mitigations even further than Windows 10. Regardless, Microsoft says on Skylake or newer chips “Intel has refined the instructions used to disable branch speculation to be more specific to indirect branches, reducing the overall performance penalty of the Spectre mitigation.”
- Windows 10 running on Skylake, Kaby Lake or newer CPU show benchmarks show “single-digit slowdowns”, but most users shouldn’t expect to see noticeable slowdowns
- Windows 10 running on Haswell or older CPUs “show more significant slowdowns” and “some users will notice a decrease in system performance”
- Windows 7 or Windows 8 running on Haswell or older CPUs means “most users will notice a decrease in system performance
Microsoft is also warning that Windows Server “shows a more significant performance impact.” So any IT admins reading this should be careful to “evaluate the risk of untrusted code for each Windows Server instance, and balance the security versus performance tradeoff for your environment.”
Apple has not responded to queries about whether the company has supplied firmware updates for the A-series iPhone chips to protect against Spectre variant 2, or even if it’s required. Google’s Android situation will rely on many different phone makers, and it’s not clear how many will require firmware updates that could have potential performance impacts. Microsoft has set an example of transparency that the rest of the industry might just have to follow.
Have Spectre and Meltdown Been Vanquished?
Microsoft has released this information as part of its commitment to “being as transparent and factual as possible to help our customers make the best possible decisions for their devices.” Which is to the company’s credit. Let’s just hope Spectre and Meltdown have been vanquished.
Have you updated your Windows PC to safeguard against Meltdown and Spectre? If so, have you noticed any effect on the performance of your computer? Are you worried about Meltdown and Spectre? Or do you consider the issue fixed? Please let us know in the comments below!