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Comment by booi | Hacker News Reader

The author makes it pretty clear this isn't a comparison of ARM vs. x86 but with the specs being nearly identical, I'm finding it very hard not to draw that conclusion. The difference is even larger when you factor in the cost difference.

Are there other factors that could explain the large performance gap?

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I think what they mean is that there are enough non-CPU differences that you can't make this an accurate comparison. That being said at the end of the day the ARM instances are cheaper and better performing—whatever the reason may be.

The SSD is clearly different. Are there other differences, or are people just assuming?

But the non CPU differences (compiler / linker / OS optimizations), number of drives etc - all seem to favor x86?

> the specs being nearly identical

graviton2 are real cores while amd/intel is SMT vCPU's. So 2x real cores difference.

Sure, but it's also 20% cheaper to get the ARM setup, so I don't think it's fair to discriminate this way. In the end what matters is what I can buy, and ARM both offers more cores per socket and per dollar.

Possibly once AWS has gotten enough people switching to Graviton CPUs, they would start raising the cost.

“Would” is a bold word choice given that AWS hasn’t ever raised prices. Could, can, might - sure.

I don't think that would work out for them. Most code that runs on AArch64 will run just as happily on AMD64. Few of their customers are going to be writing AArch64 assembly.

The cost here is an artificial variable as it completely under the control of AWS. They can decide to sell them very cheap to lock people on AWS.

Yes but porting to other ARM nodes isn't difficult, and if you're already using AWS you're comfortable with a fair bit of lock-in already.

EC2 is just virtual machines. The lock-in parts of AWS are the ones where you're not exposed to stuff like CPU architectures.

This is generally true, but in the case of ARM instances, EC2 currently has no real competitors, as far as I know.

Most software isn't cpu-architecture specific though. Switching from ARM on AWS to x86 on another providor is likely to be quite straightforward.

That's true. I'd even made the same point elsewhere :-P

https://news.ycombinator.com/item?id=25881305

Scaleway used to be one but they screwed it up and removed the offering (to be fair ThunderX1 is an early platform, not fully standards compliant etc. but argh it was working)

Packet whatever their name is now (equinox metal or something) is a competitor but only against the bare metal instances, no cheap tiny VM product unfortunately.

Huawei Cloud... has weird region restrictions for their arm offering but it exists??

Buying Annapurna Labs also means they don't have to contend with the chipmaker's margin on the Graviton chips -- Intel's margin on server chips seems to be quite high.

Nobody pays retail.

The point here is that specs are not nearly identical. Which was a premise of the comment I was replying to.

Cost is a key factor. It should be trx/$. That really makes clear the ARM advantage here.

Additionally the ARM version only had one disk vs two for x86.

I also feel like there is more headroom for optimization now that ARM is more visible as a server class target in the non-postgresql toolchains.

It's a wrong measurement because not all workload can be "shardable". If your workload is bound to a single instance it does not really matter if it's a bit cheaper.

Not every workload are behind a loadblancer, so single core / MT / single instance performance can be important.

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