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Linux 4.20 is Running Slower Than 4.19 On Intel CPUs (phoronix.com)
Freshly Exhumed writes: An intentional kernel change in Linux kernel 4.20 for enhanced Spectre mitigation is unfortunately causing Intel Linux performance to be much slower than with 4.19. That change is 'STIBP' (Single Thread Indirect Branch Predictors), which allows for preventing cross-hyperthread control of decisions that are made by indirect branch predictors. It affects Intel systems that have up-to-date microcode and CPU Hyper Threading enabled. Phoronix gives the evidence.
It's just high.
There's a joke here somewhere. If I weren't so stoned...
They say the first thing to go is your penis. Well, it's either that or your brain. I forget which...
BRING BACK MEAN LINUS
Linux kernel doesn't let your insecure and sloppy design do things that compromise the security of the OS. Sounds like a feature to me.
Remember how Jeff Bezos just recently said that once Amazon stopped focusing on customers, it was going to be the beginning of the end of Amazon? Intel stopped focusing on customers the moment it knowingly sacrificed security to maintain its near-monopoly on CPU's. While AMD has some issues with its chips, those issues pale in comparison to the wholesale don't-give-a-shit practiced by Intel.
I hope Intel has a huge, massively expensive decline.
AMD for the WIN!! will apple move mac pro over?
You *can* have both secure and faster... with AMD.
Yeah, it doesn't make sense at all. ;)
"Truth is what works" -- William James "It works!!" -- o-dark-AM comment
You can easily disable this patch with a boot command-line argument. Unless you are running a heavily VM-ed data center with shit for security, why would you cripple your system over the most esoteric hacks known to man and that - Oh! By the way! - require that you are running malware on your system already? (And spare me the horseshit about JS - that can ONLY happen in a carefully crafted environment.)
There is now a price to pay. Not really a surprise.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
Whats a Windows?
A-fucking-men.
So technically not ALL Intel cpus.. I finally dodged one of the many bullets, I should buy a lottery ticket.
No. 4.19 was insecure, but faster. 4.20 is more secure, but slower. So? If I store my passwords in plain-text it's faster. Faster still if I don't have to do a DB lookup and just hard code some that I need.
4.20 is better. The performance penalty is the cost of better security in almost all computer operations (often negligible due to faster and faster chips). Because of hardware advancements though, it's most of the time a very worthwhile tradeoff. If your application suffers that much, size up the gear.
You can disable it with a boot flag "spectre_v2=off nopti"
They usually call from India and want you to install some software on your computer since it has reported that it's being hacked. At least that is what they always say on the phone "Hello I'm calling from Windows" so that must be it.
Remember how Jeff Bezos just recently said that once Amazon stopped focusing on customers, it was going to be the beginning of the end of Amazon? Intel stopped focusing on customers the moment it knowingly sacrificed security to maintain its near-monopoly on CPU's. While AMD has some issues with its chips, those issues pale in comparison to the wholesale don't-give-a-shit practiced by Intel.
And by "knowingly" you mean Intel did this on purpose? They can be dirty as hell doing damage control, but creating Meltdown/Spectre wasn't a conscious plan or at least then I'd really like to see your documentation that security was intentionally sacrificed. And as far as I know they're not making any significant revenue on anything other than selling CPUs, they're not in the data mining business nor to they take a cut of all applications running on an Intel nor are they selling your data to third parties. And no, Intel's management engine and AMD's TrustZone and Apple's T2 all pretty much do the same thing. They're far from saints, but on the evil scale they're not nearly at the top of my list.
Live today, because you never know what tomorrow brings
I hope Intel has a huge, massively expensive decline.
I hope that Intel becomes a better company with better products and that when the dust settles they will share the x86 market roughly equally with AMD. No dirty tricks now, Intel.
When all you have is a hammer, every problem starts to look like a thumb.
It's only worthwhile in some situations.
I manage around 15,000 hypervisors which have VMs that don't ever run untrusted or arbitrary code, they aren't internet connected, etc. A 10% performance hit means millions of dollars of additional compute and network infrastructure.
And don't tell me to use AMD either, the price vs. Performance ends up being more costly at the scale and density we require.... and that's pretending we could swap existing servers out for no cost.
I thought Google had figured out a patch to circumvent this at the OS level that had negligible impact on performance?
My Other Computer Is A Data General Nova III.
When you start a program under X, it runs in a Window. You can have multiple Windows on your desktop, each with a different program running independently of each other.
It's even possible to do it in a console, with text mode programs. It's how I was first introduced to Windows on an Apple II.
https://en.wikipedia.org/wiki/Inverted_totalitarianism
Ryzenfall and related vulnerabilities still haven't been fixed
Ryzenfall is a PR exploit not a serious vulnerability, it requires physical access.
Investigators uncovered an article by Viceroy Research condemning AMD on the exploit and noted how the article was published less than half an hour after the exploits were revealed. Given the polish of the article which appears to be written many days in advance, and wording of the article which suggests that it is financially motivated, many were quick to accuse the exploit as a smear campaign engineered by Viceroy to short-sell AMD's stocks.
Meanwhile, Intel still has major issues with Meltdown, which is much more serious than Spectre because Meltdown breaks the veil between user and kernel, while Spectre is a process/process leak, much easier to address at the OS level. With fresh new Meltdown exploits demonstrated, Intel is still very much in the hot seat and AMD is the more secure processor.
When all you have is a hammer, every problem starts to look like a thumb.
I'd really like to see your documentation that security was intentionally sacrificed.
I submit the design as documentation. They do the security check after the memory access. That can only have been a deliberate decision.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
20-30% performance gain for something like 5% more transistors is nothing to sneeze at, but holy crap is it a finicky jittery fragile 20% gain that is rife with corner cases. Assuming the work load even benefits. Plenty that do not.