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Comment Re:Is there any other option, Linus? (Score 4, Interesting) 488

The reason practically every processor has the same issues is because the same optimizations we used to make processors faster had the same fundamental design error.

I mean, either someone designed the core branch predictor block and everyone worldwide copied it for every processor, or everyone implemented it differently, yet it has the same Spectre flaw, implying that the flaw is inherent in the way branch predictors work.

No. The fix is to not read from memory into the CPU cache during the speculative execution when that block of data is not there already. Changing this in the CPUs core would solve both Spectre and Meltdown, at a reasonable cost (would not defeat much current optimizations).

Comment Re:Very useful (Score 1) 153

Again, the "feature" as it is was not detailed as it had to be (basically, slows down iPhones).
Release notes said precisely at the time:
"iOS 10.2.1 includes bug fixes (...) It also improves power management during peak workloads to avoid unexpected shutdowns on iPhone". here.
It's not a like/not like issue. It's incomplete and misleading information from Apple leading people not knowing why their iPhone is slow, slowness that might be fixed thanks to a battery change.
What I don't like, though, it's people here spreading the wrong information.

Comment Re:Very useful (Score 1) 153

Not exactly. The power management as it is and how it works was not detailed in a keynote before December 2017. In iOS 10.2, "iOS 10.2 also adds a telemetry diagnostic tool that Apple can use to report battery consumption" ; the "slowdown feature" was included in 10.2.1 but it's only "On December 28, 2017 Apple acknowledged that this update changed the power management during peak workloads to avoid unexpected shutdowns on iPhone 6, iPhone 6 Plus, iPhone 6s, iPhone 6s Plus, and iPhone SE. Wikipedia source.

The feature was announced as "power management improvement" early on, but it didn't clearly detail what the side effect would be: that is, slowing down older iphones.

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