The answers to your questions for Eben Upton

Before Easter, we asked you to tell us your questions for a live Q & A with Raspberry Pi Trading CEO and Raspberry Pi creator Eben Upton. The variety of questions and comments you sent was wonderful, and while we couldn’t get to them all, we picked a handful of the most common to grill him on.

You can watch the video below — though due to this being the first pancake of our live Q&A videos, the sound is a bit iffy — or read Eben’s answers to the first five questions today. We’ll follow up with the rest in the next few weeks!

Any plans for 64-bit Raspbian?

Raspbian is effectively 32-bit Debian built for the ARMv6 instruction-set architecture supported by the ARM11 processor in the first-generation Raspberry Pi. So maybe the question should be: “Would we release a version of our operating environment that was built on top of 64-bit ARM Debian?”

And the answer is: “Not yet.”

When we released the Raspberry Pi 3 Model B+, we released an operating system image on the same day; the wonderful thing about that image is that it runs on every Raspberry Pi ever made. It even runs on the alpha boards from way back in 2011.

That deep backwards compatibility is really important for us, in large part because we don’t want to orphan our customers. If someone spent $35 on an older-model Raspberry Pi five or six years ago, they still spent $35, so it would be wrong for us to throw them under the bus.

So, if we were going to do a 64-bit version, we’d want to keep doing the 32-bit version, and then that would mean our efforts would be split across the two versions; and remember, we’re still a very small engineering team. Never say never, but it would be a big step for us.

For people wanting a 64-bit operating system, there are plenty of good third-party images out there, including SUSE Linux Enterprise Server.

Given that the 3B+ includes 5GHz wireless and Power over Ethernet (PoE) support, why would manufacturers continue to use the Compute Module?

It’s a form-factor thing.

Very large numbers of people are using the bigger product in an industrial context, and it’s well engineered for that: it has module certification, wireless on board, and now PoE support. But there are use cases that can’t accommodate this form factor. For example, NEC displays: we’ve had this great relationship with NEC for a couple of years now where a lot of their displays have a socket in the back that you can put a Compute Module into. That wouldn’t work with the 3B+ form factor.

Back of an NEC display with a Raspberry Pi Compute Module slotted in.

An NEC display with a Raspberry Pi Compute Module

What are some industrial uses/products Raspberry is used with?

The NEC displays are a good example of the broader trend of using Raspberry Pi in digital signage.

A Raspberry Pi running the wait time signage at The Wizarding World of Harry Potter, Universal Studios.
Image c/o thelonelyredditor1

If you see a monitor at a station, or an airport, or a recording studio, and you look behind it, it’s amazing how often you’ll find a Raspberry Pi sitting there. The original Raspberry Pi was particularly strong for multimedia use cases, so we saw uptake in signage very early on.

An array of many Raspberry Pis

Los Alamos Raspberry Pi supercomputer

Another great example is the Los Alamos National Laboratory building supercomputers out of Raspberry Pis. Many high-end supercomputers now are built using white-box hardware — just regular PCs connected together using some networking fabric — and a collection of Raspberry Pi units can serve as a scale model of that. The Raspberry Pi has less processing power, less memory, and less networking bandwidth than the PC, but it has a balanced amount of each. So if you don’t want to let your apprentice supercomputer engineers loose on your expensive supercomputer, a cluster of Raspberry Pis is a good alternative.

Why is there no power button on the Raspberry Pi?

“Once you start, where do you stop?” is a question we ask ourselves a lot.

There are a whole bunch of useful things that we haven’t included in the Raspberry Pi by default. We don’t have a power button, we don’t have a real-time clock, and we don’t have an analogue-to-digital converter — those are probably the three most common requests. And the issue with them is that they each cost a bit of money, they’re each only useful to a minority of users, and even that minority often can’t agree on exactly what they want. Some people would like a power button that is literally a physical analogue switch between the 5V input and the rest of the board, while others would like something a bit more like a PC power button, which is partway between a physical switch and a ‘shutdown’ button. There’s no consensus about what sort of power button we should add.

So the answer is: accessories. By leaving a feature off the board, we’re not taxing the majority of people who don’t want the feature. And of course, we create an opportunity for other companies in the ecosystem to create and sell accessories to those people who do want them.

Adafruit Push-button Power Switch Breakout Raspberry Pi

The Adafruit Push-button Power Switch Breakout is one of many accessories that fill in the gaps for makers.

We have this neat way of figuring out what features to include by default: we divide through the fraction of people who want it. If you have a 20 cent component that’s going to be used by a fifth of people, we treat that as if it’s a $1 component. And it has to fight its way against the $1 components that will be used by almost everybody.

Do you think that Raspberry Pi is the future of the Internet of Things?

Absolutely, Raspberry Pi is the future of the Internet of Things!

In practice, most of the viable early IoT use cases are in the commercial and industrial spaces rather than the consumer space. Maybe in ten years’ time, IoT will be about putting 10-cent chips into light switches, but right now there’s so much money to be saved by putting automation into factories that you don’t need 10-cent components to address the market. Last year, roughly 2 million $35 Raspberry Pi units went into commercial and industrial applications, and many of those are what you’d call IoT applications.

So I think we’re the future of a particular slice of IoT. And we have ten years to get our price point down to 10 cents :)


manuti avatar

What a pity not having 64-bit Raspbian nor power button!!

Simon Long avatar

When someone manages to convince us that 64-bit Raspbian actually offers any real advantages over 32-bit, particularly on a platform with only 1GB of memory, we might be more inclined to consider it – but as far as we can tell, it really doesn’t have any significant advantages. And as Eben points out, it would mean we would need to maintain two versions of the distro and we would lose backward compatibility – that is a very real disadvantage.

John Pitney avatar

I run InfluxDB on a Pi, and that database mmaps all of its data files. Once the sum of the data collected approaches 2 GB, the database exhausts its address space and exits. This is not an issue on 64-bit platforms, and it’s independent of the size of installed RAM.

James Carroll avatar

As mentioned above, there are 64bit options for the Pi. openSUSE has a 64 bit OS for the Pi and that should be great for DB work.

Smartroad avatar

I have wondered the same. What advantages are there for 64 bit over 32? What are people doing with a pi that could benefit from a 64 bit number?

crumble avatar

you will not loose backward compatibility if you support 32 and 64 bit. This would have much less impact than your change to systemd.

BTW normaly 64 bit mode will have more registers and more instructions. So you will have much more advantages on top of the wider address space. If you choose the right gcc version and compile against the feature set of each SoC, we will get a lot more computing power. And yes, this depends on the task and it means much more work for you. We don’t like untested software ;)

Simon Long avatar

“you will not loose backward compatibility if you support 32 and 64 bit. This would have much less impact than your change to systemd.” If we support both, we have to build and test both environments, and ship two different versions of the OS. People will not be able to remove the SD card from their Pi 3B+ and run it in their Pi Zero – which they can do now – so yes, it would lose backward compatibility. Systemd made no difference to backward compatibility – Jessie images run perfectly well on all Pi platforms.

“BTW normaly 64 bit mode will have more registers and more instructions.” No, 64-bit *processors* may have more registers and instructions; 64-bit *operating systems* generally don’t, as registers and instructions are features of the hardware, not the software. But even assuming that were true, what actual advantage would more registers and instructions offer to a typical user? Would it improve performance significantly on any common tasks in any benchmark-able fashion?

“If you choose the right gcc version and compile against the feature set of each SoC, we will get a lot more computing power.” In what way will you get “a lot more computing power”? You will have the same number of cores, running at the same speed. Your software will all be larger and will take longer to read from SD card as a result. (The 64-bit version of Windows takes up around 30% more disk space than the 32-bit version.) Reading from SD card is one of the slowest parts of any process on Pi – so it’s very hard to see that there is any actual overall benefit in performance.

As we have said several times – we have yet to see any concrete proof that a 64-bit version of Raspbian offers any significant performance improvements over the 32-bit version for the tasks for which the majority of users use their Pi. If someone can provide us with actual proof, we’ll consider this, but actual quantifiable measurements – as opposed to anecdotes – seem to be thin on the ground…

Milliways avatar

Maybe you should just produce OS with the same code, and call it 64 bit to keep those who like the big numbers happy.

Eric Olson avatar

I’m using a B+ as well as a 3B+ and it’s great that the software is the same. Thanks for the unified long term support for all models.

Graham Cummings avatar

I agree with Eben, I’d much prefer to have the cross-compatibility of the operating system across all their devices. It’s great to know that I can take a SD card out of a modern Pi and stick it into one of my older Pis. I think this is one of the things that the Pi does better than all the other SOCs out there.

Esbeeb avatar

64-bit, Shcmixty-4-bit, I say.

Asking for 64bit on a single board computer which has a RAM limitation of 1GB (which is plenty for a lightweight desktop like LXDE) is a poor use of the precious labour of the Pi Towers employees.

When I look at the awesome, super-useful, ground-breaking things that are being developed (like regular, super-useful new features in raspi-config, or the grealy-improved-in-usability LXDE-based desktop, or NOOBS, or the utility to easily set up an NFS server, allowing many PXE booting, diskless Raspberry Pi’s to connect), *I would far rather see those kinds of innovations, than a 64-bit Raspbian*.

64-bit will bring nothing tangibly better to the overall experience of using a Raspberry Pi. But if we all just let the engineers at the Pi Towers do their thing, I think that’s going to make the biggest impact, and the biggest innovation.

Eben, you’re awesome, please stick to your guns on 64bit. Your low-cost, great-quality products will benefit the most from improvements in the places that matter, not the places that don’t matter. Kudos on the B+, wth the greatly-sped-up ethernet, and vastly improved heat management, which avoids processor throttling at higher loads. Those are innovations that mater!

Esbeeb avatar

Oops, that’s “64-bit, Schmixty-4-bit, I say.”

BTW: The right time to ask for 64bit is when:
1) RAM is so cheap that 8GB of it fits into the $35 price. Then you actually need that 64bit addressing (as 32bit only addresses as high as 4GB of RAM, *but even then* you can continue using 32bit, if you use the PAE kernel hack.)
2) The 1GB RAM hard limitation that currently exists in the Pi’s SOC is completely re-engineered.
3) You want to install Raspbian on a PC, since on PC, indeed 64bit makes sense, as >4GB of RAM is frequently encountered these days. But if it’s a PC you want to use, why not just install, say, Debian (where 64bit is already offered), and not Raspbian? *Maybe that grphical NFS-server-setup utility (that Pi Towers created) should be nicely packaged upstream, eventually into Debian stable.* Or any Debian-based software developed by Pi Towers, for that matter. That would help relieve the pressure of wanting a 64-bit Raspbian (for the PC).

Eddie Maddox avatar

Esbeeb says: “… The right time to ask for 64bit is when:
… Debian (where 64bit is already offered)
… utility (that Pi Towers created) should be
nicely packaged upstream, eventually into Debian stable.*
Or any Debian-based software developed by Pi Towers
for that matter.” Agree!

If some of us need to hunt down aftermarket,
Debian based, 64-bit support, I’m OK with that,
but having all the Raspian Innovations available
in those aftermarket 64-bit solutions would be
Very Desirable.

Cuvtixo avatar

I agree, and would take it further, since the Pi is becoming, and at least partly is already, a consumer product, rather than strictly commercial or educational. There’s going to be customers who will buy a 64-bit, for status among hobbyist friends, or just because. “Throwing the past customers under the bus,” is soley the concern of an engineer; just to be real here. If you want to sell the heck out of a marketplace product, you provide the greatest selection possible; cherry coke, vanilla coke, coke zero. The previous responders need to stop looking to how practical it is to provide these extras, and look to how much they will sell, instead.

William avatar

10 cents for a fully functioning Linux board?!
I’m highly looking forward to that! ;)

Bob avatar

Can you tell us what you mean by a “fully functioning Linux board”?

Smartroad avatar

Why can’t the Zero get the CPU from the 3B+ :)

Any chance of offering the 3B+ without USB and Ethernet headers to slim it down, like the zero without the pin headers?

mahjongg avatar

because the 3B+ SoC (it’s not just a CPU) doesn’t use package on package RAM (PoP RAM).

On the 3B+ the RAM is on the bottom side of the PCB, and thats not possible with the fabrication technology of a Zero.

The Zero uses a SoC that has PoP RAM on top of it, so its small enough to fit on a Zero’s PCB, and thus cheap enough to produce for the price of a Zero.

Julius avatar

It seems I missed your call for questions. Was it posted on social media (I follow you only via the blog’s RSS)?

My question is about the availability of RPi Zero (W). Even years after its launch it is sold in limited quantities (1 RPi Zero per order, Pimoroni, or is overprized (~15€ for an zero WH, In my opinion limited quantities are more limiting than little higher prizes (maybe $6 or $7 instead of $5 for a RPi Zero without Wifi).

Why is Raspberry Pi Zero not as well available as the other Pis and will this ever become better?

Comments are closed