Windows 10 is finally getting the update we all wanted, but until it rolls out widely users are going to need to keep paying attention to Microsoft’s regular upgrade warnings. And they have struck again.
Picked up by CNet, Microsoft has confirmed it has found updates to Windows 10’s built-in Control Flow Guard (CFG) security feature which can cause massive performance issues for Google Chromium-based browsers (such as Chrome, Microsoft’s Edge browser, Vivaldi and many others). The problem was first identified by Vivaldi then replicated by Google, after which Microsoft acknowledged the issue.
How massive is massive? Tests on impacted Windows 10 PCs found Chromium performance runs 3-4x slower on average than on Windows 7, which is not affected by the issue.
“We immediately noticed performance problems. A test suite that previously took about 100 minutes to run, now took 300 or even 360 minutes,” wrote Vivaldi developer Yngve Pettersen. “[It’s a] huge Windows 10 performance issue to Chromium… One of the tests that took 100 minutes when run on Windows 10 on this machine, took 20 minutes on Windows 7.”
The fix Dawson discovered was to turn off CFG (which, as CNet notes: “shouldn’t be performed in the real world”), after which some tests were running between five and 20 times faster while one browser process ran 200 times faster.
The good news? First, Pettersen states that there is a difference between his tests and real-world usage so, while there is an impact, “it might not be as noticeable in normal use”. Second, Microsoft has identified the issue and, although it hasn’t given a specific date, believes a fix will come soon. I have asked for an update.
Until then, Windows 10 users face an all too familiar situation: feeling like test subjects for bugs which really shouldn’t have got out of beta. It also joins an infamous list of recent updates including those in October (deleting personal data), November (Windows downgraded itself), February (breaking app updates) and Awful April.
All of which only emphasises why Windows 10’s fundamental upgrade changes cannot come quickly enough.