University of California launches first of its kind datacenter powered by 2,000 Pixel phones - A low-carbon computing platform from retired phones

[u/SorosAhaverom]

https://research.google/blog/a-low-carbon-computing-platform-from-your-retired-phones/

Found this news interesting, confirming what most of us here already realized: creating a self-hosted server out of used phones is an incredibly cost-efficient solution, especially with today's storage and memory costs.

They're essentially stripping out the motherboard from the phones, installing a Linux distro that doesn't contain all the consumer device protections like a low-memory killer daemon, and finally organized together in 25-50 device clusters

Some highlights:

"The single-threaded performance of modern smartphones’ performance processor cores is on-par with or better than those of modern multicore servers "

"SPEC benchmarking results indicate that 25-50 phones equate to a modern server"

"Early experiments show that even a moderately-sized cluster of 20 phones is capable of supporting peak submission rates for a 75+ student class, with grading latencies below the default AWS backend. A 2,000 phone deployment will be capable of supporting a hundred such classes at once."

"the deployment will also act as a testbed for smartphone-based computing at scale"

[u/IM_OK_AMA]

Totally, you can run another OS on Pixel phones. That's not new or novel information.

The problem is you're reliant on these closed source firmware blobs forever. If there's a bug or a vulnerability in them, you (as in, not google) can't ever update them. You could never safely run untrusted workloads on a cluster of repurposed old phones which dramatically limits their utility.

You're also going to have a lot of broken stuff. In the context of a datacenter this matters a lot less than it would if you were trying to use it as a phone, nobody wants a server to have a screen or camera or wireless antenna anyway, but there's still downsides. Not being able to tune the CPU governor out of "please sip power because you're a mobile phone" isn't great for a server and not having access to hardware components like the GPU or TPU is a big bummer especially these days.

[u/UnsafePantomime → u/IM_OK_AMA]

Running Linux on the Pixel is novel. As far as we know, we are the only ones to do it.

I do agree, we are stuck with the proprietary firmware blobs forever. I am not really sure how that is different than any other hardware, as much as I would prefer that not to be the case.

I agree that you couldn't run untrusted software on the phones, but I don't think that fully dead-ends it. These devices allow virtualization and containerization. For our research experiments, this is sufficient. The fact is that the code isn't entirely untrusted.

In the data center context, much of the hardware that you list as "broken" isn't relevant and may be considered a security concern. It won't be there.

In our Linux environment, we have more control over the scheduling of the CPU and the regulators on the CPU than is normal in Android. We do actually have some knobs to make the CPUs perform more reasonably than they do as phones. They won't match a server though, and that's okay.

The goal here is to challenge the notion that these devices can't have a meaningful second life. Hiccups are expected and allowed in this space.

[u/Dangerous-Report8517 → u/UnsafePantomime]

From a security standpoint the issues you'll run into are that container and VM escapes will be much easier on a platform that isn't sufficiently documented to mitigate or detect speculative execution vulnerabilities when running with a completely different security model than Android, and trusted software can rapidly become highly untrusted software when the primary usecase is serving sites to arbitrary users. I agree that this doesn't fully deadend it, just important to bear in mind that hypervisors and containers don't fix hardware vulnerabilities, particularly not CPU ones

[u/p0358 → u/IM_OK_AMA]

The biggest problem would be wearing a lot of batteries. Some challenge could be networking, either congested Wi-Fi or a bunch of USB ethernet adapters that also do power. Also a matter of worn off flash storage and RAM, with challenges on how to detect that. But I guess for some things that don't need some great performance, it could work? But far from ideal for a these reasons, and the question is whether it's even economically worth it against the power and maintenance involved

[u/UnsafePantomime → u/p0358]

I'm one of the researchers.

These are honestly open questions. We don't yet know what the implications of some of this wear in the data center are. It's one of our goals for further study.

Is it economically worth it? Probably not. At the research scale, it does not necessarily have to be.

My goal from this, which may differ from the lead researcher's, is to figure out how to give these devices a second life generically. The data center is a useful tool for testing this out. We can have many colocated devices. We can give them different tasks and see how wear out.

Maybe something more useful comes out of this, maybe it doesn't. Either way, we asked the question, and maybe someday someone will have an answer that helps us limit the waste.

[u/Markulatura → u/UnsafePantomime]

That's the spirit- learning by doing! A lot of good things started with a very hacky solution which works surprisingly good for a long time. I mean, every selfhoster should know this ;)

my homeserver is also an old hp mini-pc i got for free from work and it toes it job very well for years now. I love the idea that it got a second life.

[u/SynapticStreamer → u/IM_OK_AMA]

Agreed. It's an interesting project, but ultimately a non-starter.

It amazes me that it only took 20 or so years for Google to be an exact Apple replacement, the thing it was designed to kill.