Can't wait to see before/after benchmarks for Android. Something tells me it's going to be even worse than iOS.
iPhone update for Meltdown-Spectre: before/after performance benchmarks
101–110 of 119 posts
Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks
#102Earlier quoted context omitted.
> local execution Delivered via JavaScript
So don't browse the web from your server. Why are we updating servers?
It wouldn't be the first time that a buffer overflow somewhere led to arbitrary code execution. What we're patching is a mechanism that allows escalating from unprivileged execution to reading kernel memory, and a mechanism that defeats KASLR
Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks
#103Haven'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)?
Mike Ybarra has said there's no need for them to patch the Xbox One against these attacks:
https://www.trueachievements.com/n31065/xbox-one-consoles-un...
Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks
#104I'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?
Sure, but I think that would (potentially, with the proper exploit) turn any non-root-level code-execution-able breach of your machine of a machine into a root level one, no? Maybe that's okay?
Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks
#105I will repeat these benchmarks on my iPhone 6 when I get home tonight...but in the meantime, the benchmark numbers in this article look almost exactly like the ones I had as a result of battery throttling. I bet the actual patch-related performance hit is pretty minor.
Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks
#106Can't wait to see before/after benchmarks for Android. Something tells me it's going to be even worse than iOS.
Depends on the phone. Lower end phones use cores like the A53 which don't have enough speculation HW to be affected at all.
Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks
#107Something isn't right with his benchmarks. My iPhone 6 benchmarks: Geekbench test taken on Dec 18, 2017 with iOS 11.2 Single Core: 1566 Multi-Core: 2697 Geekbench test taken on Jan 10, 2018 with iOS 11.2.2 Single Core: 1551 Multi-Core: 2675 Percentage slowdown: Single Core: 0.96% Multi-Core: 0.82%
Do you have Geekbench test with iOS 11.1.2 instead of 11.2?
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Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks
#108I'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?
I usually don't trust people. More than one have we found things improperly secured and/or exposed to the outer internet, or otherwise at risk.
We also run black-box software from third party vendors that provide compiled JAR files which is directly related to this fuss. Last thing I'd like to have is another attack vector at home.
Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks
#109This 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…
I just did a 11.2.1/11.2.2 benchmark of my iPhone 7: https://browser.geekbench.com/v4/cpu/compare/6303880?baselin...
The result is that 11.2.2 is slightly faster than 11.2.1 (around 2%).
And here’s one of my iPad Pro 10.5”: https://browser.geekbench.com/v4/cpu/compare/6304146?baselin... (0.9% increase in performance).
Re: iPhone update for Meltdown-Spectre: before/after performance benchmarks
#110Ok, 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.
From Geekbench knowledgebase: "Geekbench will use AES instructions when available, and fall back to software implementations otherwise."
I expect this test to use them.