This article doesn't make any sense. The author is doing generic phone benchmarks. But the Spectre fix is a webkit fix only, not an OS-wide fix. If they're seeing performance regressions across the whole OS because of fixing Spectre, something's seriously wrong with their benchmark methodology.
Edit: The author upgraded from iOS 11.1.2 to iOS 11.2.2. This isn't just a test of the Spectre fix. The most likely explanation here is upgrading to iOS 11.2 caused their iPhone 6 to start throttling due to battery wear (11.2 added throttling to iPhone 7, and it's plausible that it changed the conditions for throttling on iPhone 6). It's also possible that this is instead caused by the Meltdown patch, but these numbers are still way out of line with what was expected for Meltdown on iOS, whereas they're very much in line with what we've been seeing with battery throttling.
>> a significant decrease in performance on the iPhone 6 up to 50%
Something's up. I updated my 6S yesterday and have noticed zero in performance changes or battery loss. Still plenty of bugs though, I was reading an email and the 'flag/file/trash/reply/new' bar totally went away. At least the touchscreen hasn't gone unresponsive, causing me to have to hit sleep/wake to toggle it back on. Maybe they finally fixed that.
Ok, I'm sceptical about the results. The reason is that there doesn't seem to be a massive difference between the tests. Since this fix is about speculative exec, why would it affect crypto code which is very register based and branchless as much as sqlite which is full of branches and memory/storage based? Why would it affect AES which is hardware accelerated as much as integer processing which is not?
I'm not saying this is impossible - maybe there's something that I'm missing. But it just doesn't add up at the moment. I'd love a more detailed / repeatable test.
I've went through Denial, Anger, Bargaining, and now in an Acceptance stage after taking up to 31% performance hit on some of services managed by my team. Worst case has been Elasticsearch so far with our load pattern, taking that 31% hit.
Oh well, too bad, enjoying the ride.
I made similar benchmarks recently on my iPhone 6S, running iOS iOS 11.1.2 vs 11.2.1, before and after replacing the battery:
TLDR: It's 11.2.1 that is throttling the older iPhones, because of the battery wear.
Sample size of 1, but I Geekbench'd my iPhone X before and after upgrade.
11.2.1: Single-Core 4137, Multi-Core 9315
11.2.2: Single-Core 4039, Multi-Core 9876
Anecdotally as well, I haven't seen a noticeable difference in performance. So your mileage may vary substantially based on what device you have.