iPhone update for Meltdown-Spectre: before/after performance benchmarks • Hacker News Board

Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks

#91

Post by codazoda » Wed, Jan 10, 2018, 8:47 PM UTC

hueving wrote: post #67

toomuchtodo wrote: post #50

Earlier quoted context omitted.

All major cloud providers are buying renewables for their operations. Yay? At least the additional renewable generation capacity built out will exist for decades (while processors should become more efficient as these security issues are addressed and new hardware rolls out).

>All major cloud providers are buying renewables for their operations. Yay? Not yay. This is an overnight massive bump so they are going to consume from the same existing pool of renewables, forcing utilities to use more non renewables to make up for the demand difference. Also, even when they do build out the renewable generation to make up the difference, it's still environmentally a problem due to the manufacturin…

I've read a few articles saying that there is so much Solar adoption in the U.S. that there is a surplus at some times (summer days I believe). It use to be that there was too much use from home AC systems so power was expensive during the day. It seems to be switching to night now as so much is generated during the day (with just 3% adoption of rooftop Solar).

Here's an example of one article on the matter, which I just skimmed a little.

http://www.latimes.com/projects/la-fi-electricity-solar/

I'm guessing that CPU's use a whole lot less electricity than things like AC systems, so they probably don't affect total electricity used by that much. I was able to surmise that a 3 ton central air conditioner uses around 3500 watts per hour while an Intel I7 (whole system) uses around 150 watts per hour.

My theory, then, is that this won't affect total power use in the U.S. all that much.

Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks

#92

Post by cma » Wed, Jan 10, 2018, 8:48 PM UTC

eridius wrote: post #87

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 explana…

What sucks is there is no way to fix Spectre without going the battery throttled version.

Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks

#93

Post by reaperducer » Wed, Jan 10, 2018, 8:49 PM UTC

dboreham wrote: post #75

euph0ria wrote: post #14

I wonder how much extra revenue this will bring to AWS/GCP etc selling more instances to cover the performance loss on servers?

I'm guessing more than 1/2 of all AWS instances are idle. Probably 10% are systems nobody knows anything about, whoever started them left the company..

Add the 5% that are nothing but public garbage bins for personal information collected by various companies and intelligence agencies, just waiting to be discovered!

Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks

#94

Post by Terribledactyl » Wed, Jan 10, 2018, 8:50 PM UTC

viraptor wrote: post #57

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 sayin…

The A8 doesn't have a dedicated crypto engine like Intel chips do (uncore I think they call it). The A8 does have a couple of AES specific instructions so each core can speed up the work, but they were executed speculatively and presumably are no longer done so.

Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks

#95

Post by makeramen » Wed, Jan 10, 2018, 8:50 PM UTC

viraptor wrote: post #57

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 sayin…

These benchmarks are between iOS 11.1.2 and 11.2.2, which include the battery throttling code in 11.2.0.

We need a benchmark between 11.2.1 and 11.2.2 instead.

Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks

#96

Post by eridius » Wed, Jan 10, 2018, 8:50 PM UTC

cma wrote: post #92

eridius wrote: post #87

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 explana…

What sucks is there is no way to fix Spectre without going the battery throttled version.

Yeah there is. Get your battery replaced. Apple will replace your battery for $29 (as long as there's sufficient wear, but if you're seeing throttling, you're well past the cutoff).

Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks

#97

Post by apohn » Wed, Jan 10, 2018, 8:51 PM UTC

I just updated my 6+ and ran Geekbench before and after. No major difference in scores and the single and multi-core benchmarks are consistent with the comparison numbers for other 6+ phones. Battery is in good health.

Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks

#98

Post by [deleted] » Wed, Jan 10, 2018, 8:53 PM UTC

Negative1 wrote: post #76

Haven't seen much coverage on how this affects game consoles like the Xbox and Playstation (which use AMD CPUs). Does anyone know if they've talked about patching it and how this would affect game performance (which is a pretty big deal for gamers who expect a consistent experience)?

[deleted]

Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks

#99

Post by ianstormtaylor » Wed, Jan 10, 2018, 8:53 PM UTC

eridius wrote: post #87

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 explana…

This.

The article should be flagged off the front page or edited by the mods to show that it's questionable.

This is a single person's test results, across versions that are known to have touched the battery/CPU slowdown logic, showing insane performance degradation across almost every aspect of the phone... it's super questionable. And right now it's #1 on HN despite all of that, just spreading misinformation.

Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks

#100

Post by mrmondo » Wed, Jan 10, 2018, 8:53 PM UTC

I’ve more than a little skeptical of these results, I too am very disappointed in major CPU vendors (especially their PR and management teams), but these results seem more than a little smelly.

I am what I’d consider a heavy iOS user on multiple devices and I don’t believe I’ve honestly noticed any difference at all. If these results were correct, I believe I’d notice at least a 10-15% decrease in performance - but no. What I haven’t looked at is battery life so I cannot comment on that.