How to make Linux run fast again on Intel CPUs

Re:How to make Linux run fast again on Intel CPUs by bonzini on Sunday October 13, 2019 @12:29PM (#21241241)

It takes time. Look closely and you will see that some cloud providers are sending out patches for things such as AMD-specific KVM code. Maybe they will not even ever reach feature parity in their offerings, but at least we can understand that interested customers exist, and it is surely sending signals to Intel.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by innagadadavida on Sunday October 13, 2019 @04:02PM (#21242566)

Perhaps much of their workload is io bound and they didn’t notice a thing?

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by takeda on Sunday October 13, 2019 @05:12PM (#21243071)

I would think that would actually benefit companies like AWS. Patches for the bug causes applications to run slower, because of that their customers will be forced to use bigger instances and bigger instances cost more.

I suppose only loss for AWS would be if someone decides to move back to own data center because of that, bit I don't think this would cause that.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by alexgartrell on Sunday October 13, 2019 @06:27PM (#21243607)

I don't work at AWS (and haven't) but I do work in the world of big infra and my wild-ass guess is that the user stuff in AWS doesn't run as consistently hot as the SaaS stuff that Amazon runs itself.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by softawre on Monday October 14, 2019 @04:24PM (#21252454)

Agreed. We run at like 11% average CPU usage across 5k+ EC2 instances in AWS.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by Godel_unicode on Sunday October 13, 2019 @02:24PM (#21241909)

Why would that be the case? AWS makes no guarantees about the performance of their instances. If everything gets slower, the most likely thing that happens is high-scale customers need a correspondingly higher number of servers to handle their load.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by Rapzid on Sunday October 13, 2019 @02:55PM (#21242133)

AWS will care about performance per KW/h.

They also have in the past at least advertised the specific processor models different instance types use. Information is sprinkled around so that people who care can know what to expect..

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by spurdoman77 on Sunday October 13, 2019 @02:55PM (#21242127)

Aws has a very nice lock in for their customers. They dont have to care much.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by dragonwriter on Sunday October 13, 2019 @05:15PM (#21243095)

> AWS makes no guarantees about the performance of their instances. I

They do for services that are higher-level than EC2, where cost/performance assumptions about the underlying instances used are built into the cost structure.

AWS tries very hard to get customers onto those higher-level managed services I stead of rolling their own on EC2.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by RachelF on Monday October 14, 2019 @12:05AM (#21245202)

Not only were there few repercussions for Intel, their CEO and some on his team faced few repercussions too.

What amazed me is how Intel execs avoided insider trading charges from the SEC when they sold their own Intel shares, knowing of the problems themselves, but before it was public knowledge.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by devwastaken on Sunday October 13, 2019 @03:18PM (#21242299)

The Intel vulnerabilities are a matter of national security across the world. If you can use a known exploit to take complete root access at a hardware level, just by running some Network requests on the local network - imagine what a foreign government could do if they wanted.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by alerighi on Monday October 14, 2019 @05:28AM (#21246415)

Because a system is secure as long as somebody doesn't break it. If tomorrow someone comes with an algorithm that can factor a prime number in polynomial time RSA will be useless basically, but since then we consider it secure.

Beside that, all these vulnerabilities comes from optimizations done by the CPU. The only reliable way to avoid them is not to have the optimizations to start with, and that is what mitigations do.

It's the choice of the user to choose if he wants or not the mitigations, I personally have `mitigations=off` on my machines because I think that the security threat is not so big for my workflow.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by yellowapple on Monday October 14, 2019 @06:41PM (#21253637)

I can't speak for everyone who's ever used an Intel CPU, but Intel's certainly lost my tiny fraction of market share to AMD, at least for desktops (AMD laptops with solid specs seem to be rather unfortunately rare); switched from Intel + Nvidia to AMD + AMD when I built my latest rig, and haven't looked back.

Granted, in my case it was less about CPU security issues (some - though certainly not all - of which also impacted AMD and ARM CPUs, from what I understand) and more about AMD getting me way better bang for my buck (and also, because I wanted to try out a Threadripper and my God am I glad I did), but still.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by gameswithgo on Sunday October 13, 2019 @12:58PM (#21241390)

they are rapidly losing market share to amd right now

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by cheez on Sunday October 13, 2019 @02:24PM (#21241911)

Intel has been here before, they will persevere. I type this using a AMD CPU.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by Godel_unicode on Sunday October 13, 2019 @02:26PM (#21241926)

Is that true in server chips? I know AMD has gotten design wins from e.g. Microsoft Surface, but I've seen nothing to indicate an appreciable change in server sales.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by jagger27 on Sunday October 13, 2019 @05:35PM (#21243234)

It is especially true in server chips. AMD offers double the cores per watt of TDP at roughly half the price at the same IPC.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by p1necone on Sunday October 13, 2019 @05:46PM (#21243326)

Have they actually gained much market share in the server space though - big corps don't move very quickly, even when the options are way more competitive. "Nobody ever got fired for choosing Intel" and so on.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by shifto on Monday October 14, 2019 @05:07AM (#21246344)

Dell and HP are having trouble sourcing Intel CPU's and started rolling out way more AMD machines. Customers needing a new machines don't have a lot of options and has resulted in AMD having about 1% server market share to about 10% in just months.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by jagger27 on Sunday October 13, 2019 @06:42PM (#21243724)

The thing about Intel’s sales dept is that they are able to muscle big clients with incentives from their “make comp” fund. Remember the lawsuit from years ago about Intel paying Dell not to buy AMD products? They’re still doing that, and haven’t paid that fine yet.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by p1necone on Sunday October 13, 2019 @09:07PM (#21244472)

Surely if they have the funds to bribe companies into picking intel, they could instead be using that money to make their offerings on par with AMD $/performance wise instead?

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by guenthert on Monday October 14, 2019 @12:39PM (#21250133)

Well, I'm not sure what to make of these "cores per watt of TDP" and I suspect few will. SPEC has the "power" benchmark, measuring the performance of a Java server and relating it to the electrical power needed for that.

Seems to me that systems based on AMD's EPYC are doing considerably better in this benchmark than those using Intel CPUs: http://spec.org/power_ssj2008/results/res2019q3/

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by zaarn on Monday October 14, 2019 @09:22AM (#21247934)

Atleast from what I've seen in SMB; we have been buying AMD. Plenty of AMD. For our servers.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by Guthur on Sunday October 13, 2019 @06:19PM (#21243554)

It is a perfect opportunity for AMD, unfortunately it looks like there isn't the manufacturing capacity at TSMC on 7nm for them to fully exploit the situation.

The recent delays and high prices in high-end consumer ryzen appears to point to AMD trying to satisfy and increasingly high demand for rome epyc.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by earenndil on Sunday October 13, 2019 @09:45PM (#21244642)

Know someone who works on AWS. Says it hasn't affected them at all.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by ahbyb on Sunday October 13, 2019 @01:14PM (#21241479)

In all my computing life every time I've bought something from AMD (be it a CPU or a GPU) I've regretted it. It's going to take me some time to get over that.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by trollied on Sunday October 13, 2019 @01:23PM (#21241523)

I bought a K6. It was amazing compared to Intel at the time . No regrets

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by tuananh on Monday October 14, 2019 @03:20AM (#21245909)

i bought the latest ryzen. very satisfied with the purchase so far :)

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by moocowtruck on Sunday October 13, 2019 @12:17PM (#21241179)

because the alternatives really are not alternatives, and because moving from something like investments in hardware are not quick and easy moves. I will tell you once or if ppl figure out then the drain will be pulled for intel

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by gameswithgo on Sunday October 13, 2019 @01:02PM (#21241408)

as of pretty recently epic is better by almost all metrics.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by bonzini on Sunday October 13, 2019 @01:45PM (#21241651)

KVM maintainer here. Virtualization still has slightly better overhead on Intel for several workloads. Even with all mitigations enabled (they hardly affect AMD times), AMD is sitting at about 3000 clock cycles vs 2000 for Intel.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by sascha_sl on Sunday October 13, 2019 @01:46PM (#21241664)

I've never heard about this, genuinely curious what workloads those are.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by bonzini on Sunday October 13, 2019 @02:40PM (#21242020)

Anything that causes the guest to go to sleep (HLT) a lot, for example message passing between two processes on two different VMs. You can try TCP_RR from netperf.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by sascha_sl on Sunday October 13, 2019 @01:46PM (#21241657)

In all, unless you use Optane. Which you might on database servers with large infrequently accessed datasets? Can't really think of many use cases where throwing in an NVMe drive isn't better.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by detail-oriented on Sunday October 13, 2019 @01:58PM (#21241748)

I'm currently pricing out a new home workstation build, not looking at intel parts.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by hannob on Sunday October 13, 2019 @01:45PM (#21241654)

I don't have the overall impression that AMD/ARM are significantly less affected by all those issues.

There were a few intel specific fuckups. Maybe more, maybe more people were looking. But the core problem is deeply embedded in how CPUs were built for decades.

[ Parent | on HN ]

Re:How to make Linux run fast again on Intel CPUs by zamadatix on Sunday October 13, 2019 @01:54PM (#21241724)

AMD and most ARM CPUs weren't vulnerable to the entire Meltdown class of issues.

https://openbenchmarking.org/embed.php?i=1907066-HV-MITIGATI... from https://www.phoronix.com/scan.php?page=article&item=3900x-99...

[ Parent | on HN ]