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

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

#71

Post by hueving » Wed, Jan 10, 2018, 8:32 PM UTC

paws wrote: post #37

My iPhone X has been on 11.2.5 since the day it came out, and I haven't perceived any slowdowns. Have not done any benchmarking, and I'm not saying performance is the same as before, but anecdotally I haven't seen a difference. Just one guy's opinion.

Do you game or do anything CPU intensive?

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

#72

Post by euroclydon » Wed, Jan 10, 2018, 8:33 PM UTC

FBISurveillance wrote: post #2

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.

What about using dedicated hardware and not running the patches? At attacker has to run malicious code on your server to exploit the vulns anyhow, right?

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

#73

Post by jackson1way » Wed, Jan 10, 2018, 8:33 PM UTC

paws wrote: post #37

My iPhone X has been on 11.2.5 since the day it came out, and I haven't perceived any slowdowns. Have not done any benchmarking, and I'm not saying performance is the same as before, but anecdotally I haven't seen a difference. Just one guy's opinion.

the latest iOS version as of today is 11.2.2

I don't think 11.2.5 exists

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

#74

Post by delish » Wed, Jan 10, 2018, 8:34 PM UTC

oatmealsnap wrote: post #63

ponchoalv wrote: post #41

Earlier quoted context omitted.

same behaivor here... no perfomance / battery hit.

6 or 6s?

I have a 6S+. I noticed a performance gain going from 11.2.1 to 11.2.2.

Before: 2384.

After: 2541.

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

#75

Post by dboreham » Wed, Jan 10, 2018, 8:34 PM UTC

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..

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

#76

Post by Negative1 » Wed, Jan 10, 2018, 8:35 PM UTC

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)?

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

#77

Post by euroclydon » Wed, Jan 10, 2018, 8:36 PM UTC

mkagenius wrote: post #66

qeternity wrote: post #29

Earlier quoted context omitted.

All of these issues require local execution. It’s perfectly fine for many single user, performance critical use cases to make this type of security trade off.

> local execution Delivered via JavaScript

So don't browse the web from your server. Why are we updating servers?

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

#78

Post by scott_s » Wed, Jan 10, 2018, 8:38 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…

I can't speak about these benchmarks (the site is down). But Meltdown is not about speculative execution, it's about out-of-order execution. The fixes for Meltdown involve getting kernel data out of user virtual memory, and flushing the TLB if the processor does not have the pcid instruction. So context switches - including system calls - will tend to be more expensive, and if the processor does not implement pcid, way more expensive.

See https://meltdownattack.com/. I haven't yet read the Spectre paper, but I can say that the Meltdown paper is very readable and walks readers through everything. I anticipate the Spectre paper is as well.

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

#79

Post by rconti » Wed, Jan 10, 2018, 8:38 PM UTC

jasonlotito wrote: post #45

rconti wrote: post #6

Why does Cloudflare tell me I'm able to browse a snapshot while the site is offline, but there is no snapshot?

I've never known Cloudflare to do things well. It's the last CDN I'd want to use. Edit: For example, the 502 page is showing, but supposedly, you are supposed to see the site based on this: "However, because the site uses Cloudflare's Always Online™ technology you can continue to surf a snapshot of the site."

Yeah, this is the first time I've ever seen the "you can continue to surf a snapshot of the site" message along with the 502 though. Or maybe I've just never looked that closely.

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

#80

Post by schneidmaster » Wed, Jan 10, 2018, 8:40 PM UTC

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.