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SSDs have become fast, except in the cloud

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Re: SSDs have become fast, except in the cloud

#291

This was a huge technical problem I worked on at Google, and is sort of fundamental to a cloud. I believe this is actually a big deal that drives peoples' technology directions. SSDs in the cloud are attached over a network, and fundamentally have to be. The problem is that this network is so large and slow that it can't give you anywhere near the performance of a local SSD. This wasn't a problem for hard drives, whi…

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Re: SSDs have become fast, except in the cloud

#292
post #260

Earlier quoted context omitted.

the tests were for these local (metal direct connect ssds). The issue is not network overhead -- its that just like everything else in cloud the performance of 10 years ago was used as the baseline that carries over today with upcharges to buy back the gains. there is a reason why vcpu performance is still locked to the typical core from 10 years ago when every core on a machine today in those data scenters is 3-5x o…

vcpu performance is still locked to the typical core from 10 years ago No. In some cases I think AWS actually buys special processors that are clocked higher than the ones you can buy.

You are talking about real CPU not virtual cpu

Re: SSDs have become fast, except in the cloud

#293
post #199

Earlier quoted context omitted.

That's the abstraction they want you to work with, yes. That doesn't mean it's what is actually happening - at least not in the same way that you're thinking. As a hint for you, I said " a network", not " the network." You can also look at public presentations about how Nitro works.

I've linked to public documentation that is pretty clearly in conflict with what you said. There's no wiggle room in how AWS describes their service without it being false advertising. There's no "ah, but what if we define the entire building to be the host computer, then the networked SSDs really are inside the host computer" sleight of hand to pull off here. You've provided cryptic hints and a suggestion to watch s…

You are correct, and the parent you’re replying to is confused. Nitro is for EBS, not the i3 local NVMe instances.

Those i3 instances lose your data whenever you stop and start them again (ie migrate to a different host machine), there’s absolutely no reason they would use network.

EBS itself uses a different network than the “normal” internet, if I were to guess it’s a converged Ethernet network optimized for iSCSI. Which is what Nitro optimizes for as well. But it’s not relevant for the local NVMe storage.

Re: SSDs have become fast, except in the cloud

#294
post #218

Earlier quoted context omitted.

That's the abstraction they want you to work with, yes. That doesn't mean it's what is actually happening - at least not in the same way that you're thinking. As a hint for you, I said " a network", not " the network." You can also look at public presentations about how Nitro works.

it sounds like you're trying to say "PCI switch" without saying "PCI switch" (I worked at Google for over a decade, including hardware division).

That is what I am trying to say without actually giving it out. PCIe switches are very much not transparent devices. Apparently AWS has not published anything about this, and doesn't have Nitro moderating access to "local" SSD, though - that I did get confused with EBS.

Re: SSDs have become fast, except in the cloud

#295

Earlier quoted context omitted.

I could not be more confused. Does EC2 quietly call their hosting machines "droplets"? I knew "droplets" to be a DigitalOcean team, but DigitalOcean doesn't have Nitro cards.

Now I'm wondering if that's where DO got the name in the first place

Surely "droplet" is a derivative of "ocean?"

Re: SSDs have become fast, except in the cloud

#297

Earlier quoted context omitted.

It's because the "local" SSDs are not actually physically attached and there's a network protocol in the way.

That seems like a big opportunity for other cloud providers. They could provide SSDs that are actually physically attached and boast (rightfully) that their SSDs are a lot faster, drawing away business from older cloud providers.

This is already a thing. AWS instance store volumes are directly attached to the host. I’m pretty sure GCP and Azure also have an equivalent local storage option.

Re: SSDs have become fast, except in the cloud

#298

Earlier quoted context omitted.

That seems like a big opportunity for other cloud providers. They could provide SSDs that are actually physically attached and boast (rightfully) that their SSDs are a lot faster, drawing away business from older cloud providers.

For what kind of workloads would a slower SSD be a significant bottleneck?

I run very large database-y workloads. Storage bandwidth is by far the throughput rate limiting factor. Cloud environments are highly constrained in this regard and there is a mismatch between the amount of CPU you are required to buy to get a given amount of bandwidth. I could saturate a much faster storage system with a fraction of the CPU but that isn’t an option. Note that latency is not a major concern here.

This has an enormous economic impact. I once did a TCO study with AWS to run data-intensive workload running on purpose-built infrastructure on their cloud. AWS would have been 3x more expensive per their own numbers, they didn’t even argue it. The main difference is that we had highly optimized our storage configuration to provide exceptional throughput for our workload on cheap hardware.

I currently run workloads in the cloud because it is convenient. At scale though, the cost difference to run it on your own hardware is compelling. The cloud companies also benefit from a learned helplessness when it comes to physical infrastructure. Ironically, it has never been easier to do a custom infrastructure build, which companies used to do all the time, but most people act like it is deep magic now.

Re: SSDs have become fast, except in the cloud

#299

Earlier quoted context omitted.

Now I'm wondering if that's where DO got the name in the first place

Surely "droplet" is a derivative of "ocean?"

Clouds (like, the big fluffy things in the sky) are made up of many droplets of liquid. Using "droplet" to refer to the things that make up cloud computing is a pretty natural nickname for any cloud provider, not just DO. I do imagine that DO uses "droplet" as a public product branding because it works well with their "Ocean" brand, though.

...now I'm actually interested in knowing if "droplet" is derived from "ocean", or if "Digital Ocean" was derived from having many droplets (which was derived from cloud). Maybe neither.

Re: SSDs have become fast, except in the cloud

#300
post #262

Earlier quoted context omitted.

In the startup world, this is correct. The success that VCs are after is when your customer base doubles every month. Better yet, every week. Having a reasonably scalable infra at the start ensures that a success won't kill you. Of course, the chances of a runaway success like this are slim, so 99% or more startups overbuild, given their resulting customer base. But it's like 99% or more pilots who put on a parachute…

You aren't going to get there. The risks and complexity of a startup are high to begin with. Adding artificial roadblocks because of aspirational fantasies is going to hold you back. Look at the big successes such as youtube, twitter, facebook, airbnb, lyft, google, yahoo - exactly zero of them did this preventatively. Even altavista and babelfish, done by DEC and running on Alphas, which they had plenty of, had to b…

Do you remember the companies that did not scale? friendster did well until it failed to scale, and Facebook took over.

So the converse argument might be: don't bungle it up because you failed to plan. Provision for at least 10x growth with every (re-)implementation.

https://highscalability.com/friendster-lost-lead-because-of-...

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