Rui Carmo
July 14^th 2019, at lunchtime · 5 min read

Notes On The Raspberry Pi 4

Of course I ordered one. I did it partly because I need to plan ahead for replacing my ageing ODROID U2, which has been the main house server for nearly six years (since it was the only ARM device I had with 2GB of RAM), and partly because my lab setup (which runs on a 3B+) is a little short on RAM.

Even though I don’t own a sample of every single Raspberry Pi model, I’ve gone through enough board revisions to know that there will be teething issues (like the current USB power intake), so this was a calculated bet.

I got the 4GB model intending to use it as a direct replacement for my lab machine, and was amused to see that the Safety and User Guide that comes in the box with it actually says Raspberry Pi 4 Model B 1GB, 2GB, 4GB + 8GB variants – but the 8GB bit is said to be a typo, since there are currently no matching RAM chips that would fit the current design.

Not wanting to bore you with a full review (there are zillions of them out there by now), here are my impressions:

The Good Bits

It is markedly faster on all counts, even compared to the last CPU revisions of the 3+ boards. I moved the latest SD card I had (already running Raspbian Buster) from a 3A+ to the 4B and the Docker containers I was running there were much snappier, even via Wi-Fi.
The 4GB of RAM mine comes with mean that the Arduino IDE, Mathematica and Firefox ESR (which is what I prefer to use instead of Chromium), as well as an ARM custom build of VS Code, are all usable simultaneously.

In comparison with the 3B+ and 3A+ (which, as I’ll explain later, are now my staple devices), it is a pretty solid upgrade, but…

Pitfalls

It has no on-board flash/eMMC, which is (together with its 2GB of RAM) one of the main reasons the ODROID U2 is still the house server. SD cards are amazingly resilient these days, but performance is still uneven and I don’t want to run 24/7 off them.
The form factor is mostly the same. Irritatingly, though, the Ethernet port swapped sides, which means the former official case (which has pop-out panels on the sides) cannot be re-used at all. I have two of those in black I can carve into suitable replacements, but…
The thermal envelope is definitely an issue, and from what I’ve seen the official case doesn’t account for airflow or any form of cooling, so I’m waiting on a couple of 5V 30mm fans and tweaking the STL files for this case in the meantime.

I’ve been browsing through pieces like Tom’s Hardware and other active/passive cooler comparisons, and the inescapable conclusion seems to be that you need some decent cooling to run the thing with a case.

vcgencmd reports 56-59°C in my office when idle, i.e., with all services except ssh shut down, and accessing it via Wi-Fi, which is sort of OK.

But it gets too hot for my liking under load, especially considering that it’s 27°C outside now and that Summer heat around these parts usually rises way above 40°C, and the prospect of having fan noise in my office again after years of quiet machines isn’t one I relish.

Stuff I’m not going to Use (Yet)

Dual micro-HDMI out. I haven’t plugged mine in to any kind of monitor yet and am curious about the potential for digital signage, but right now that’s not a priority (I think I have the right cable someplace, but most of my use is via SSH/RDP/VNC, so I haven’t bothered).
I don’t expect to make much use of USB 3 (but I’ll be keeping an eye on the in-progress USB firmware fixes that aim to lower heat output as well).
PoE/GPIOs are not something that I’m likely to use with this board either–all the hardware stuff I do these days tends to be a lot simpler, and an ESP8266 is often enough.

The Sweet Spot

So, what would I improve (besides thermals and storage)?

Well, I’d probably like to see a 4A revision of this–or, without doing any major CPU revisions, a Zero-sized board with a 3A+ CPU and more RAM, since my main “production” use cases right now are:

A “lab” station with 1-2 USB ports for plugging in an USB oscilloscope and/or FTDI adapters for flashing MCUs of various sorts (currently a 3B+) and needs all the RAM it can get.
A home automation server to run homebridge and a number of other Docker containers and plug in a single ZigBee SDR dongle (currently an ODROID U2), which requires a minimum of 2GB of RAM and (ideally) eMMC storage.
A Docker registry/build server that runs off a single USB external disk (currently a 2B) and needs more CPU and RAM.
A HomeKit camera running off a Zero W (which badly needs more CPU power).

That is besides the IoT/MCU stuff (which is better handled by the ESP8266/ESP32 devices I’m using these days), so there’s a yawning gap between what I need and what I got with the 4B.

Then there’s the “toy” stuff (for instance, my previous lab 3B was turned into a game console running Lakka for the kids with Bluetooth controllers), but that’s besides the point–there’s a trend here for the sweet spot (as far as I’m concerned) being somewhere in the middle.

The A Team

I recently got two Pi 3A+ boards (the same CPU as the 3B+, but only 512MB of RAM) and find them a great compromise between CPU speed and expandability (even with only the one USB A port). I also went and got a Banana Pi M2-Zero to see if I could have the same experience in a smaller package¹:

From left to right, the Banana Pi Zero, a Zero W, one of my 3A+ boards with a ReSpeaker Mic Array, and the 4B

The 3A+ above is currently running a voice recognition shim (I’m really interested in building something that will do basic voice commands completely on-device), and I hijacked its sibling (which was destined to other purposes) into a sort of “portable Linux sidecar” for my iPad following this fad from a couple of weeks back.

And for me, the A series makes the most sense. I like the smaller form factor a lot, (mostly) don’t need the extra USB ports (or even Ethernet) and all I really need right now (taking the 3A+ as an example, and covering 100% of my use cases above) is a 4A board with 2GB RAM and an eMMC flash–something that is tantalizingly feasible now.

I would also love to see a 64-bit version of the OS (I’ve been tinkering with various kinds of ARM servers) but the move to Debian Buster as a base, even if a little premature, seems to have fixed a lot of my annoyances.

And that’s it. Time to go back to cloud orchestration and more impacting stuff, I’ve fallen behind schedule on most of my personal projects (as usual)…

I didn’t succeed. The Banana Pi is a disaster in terms of OS support, and mine hasn’t booted to a stable state once yet. Don’t buy it. ↩︎

Rui Carmo
July 4^th 2019, at teatime · 1 min read

Apple is reportedly giving up on the MacBook keyboard ※

And there was much rejoicing throughout the land, for people would be able to trust their primary input devices once more.

Rui Carmo
June 28^th 2019, at dawn · 1 min read

Jony Ive Is Leaving Apple ※

There have been hints (and there will be no end of “no more TouchBar/better keyboard” jokes) but this is both interesting timing and probably long overdue.

Like Gruber points out, Apple’s product pipeline and planning cycle is long enough for the effects to be latent, but it is still something to worry about in this age of relentless business operations Tim has brought to the company.

After all, if both your software and hardware innovation starts petering out, you lose your competitive edge.

Or, like Steve would have probably said, your soul.

Rui Carmo
June 27^th 2019, at dawn · 1 min read

Tether RPi to iPad Pro via Ethernet over USB-C ※

I’ve done this via Wi-Fi, obviously, but a direct Ethernet-over-USB connection is something I never tried from an iPad, and it should also work with Lightning devices (and the right dongles). And its been possible for ages, so I’m partially kicking myself for never having tried it.

Would be nicer to do it via Bluetooth, though, and, in a perfect world, to something that was the same size as the Zero but with more CPU.and RAM–or, you know, to an actual UNIX userland inside the iPad…

Update: It was much easier than I thought to get Bluetooth PAN to work for Raspbian Stretch and Buster alike. here’s a gist with the required config, works great to SSH to pi.local (which gets automatically announced via Rendezvous).

Rui Carmo
June 24^th 2019, at dawn · 1 min read

Raspberry Pi 4 ※

This is awesome, and a very welcome upgrade. I wish they’d added some on-board storage instead of the extra HDMI out (2GB of RAM and a little flash would have been the sweet spot for me), but 4GB RAM is way above what I expected for this iteration, and if I could spare the cash I’d buy a half-dozen and build myself a new cluster.

But this will be a killer solution for digital signage (time to dust off the stuff I wrote years back for Codebits and PixelsCamp, perhaps?).

Rui Carmo
June 20^th 2019, at night · 7 min read

Scheme-ing

Last Sunday I spent a few hours revisiting LISP-related languages, partly because I miss writing Clojure and partly because I wanted to do a relatively simple thing: issue a bunch of HTTPS requests, collate the resulting JSON data and then issue a final POST request. And I wanted to do it with an HTTP library that didn’t suck, in the smallest possible amount of space, and with a static binary. Two out of three wouldn’t be bad, right?

Rui Carmo
June 18^th 2019, at breakfast · 1 min read

The Future of Docker Desktop for Windows ※

Considering that Docker Desktop has been feeling largely neglected for a long while (I subscribe to a handful of long-standing bugs, and keep having to remove the auto-start registry keys it insists on leaving behind), this is a good thing.

But the best thing for me is that, with WSL 2, you have zero need for it if (like me) you live inside a terminal, and I wish the same were effectively possible on the Mac (which it mostly is, but I don’t want to maintain my own HyperKit hacks).

Rui Carmo
June 15^th 2019, in the afternoon · 7 min read

Making k3s Self-Aware

Over the past couple of bank holidays I’ve kept playing around with k3s, which is a fun way to take my mind off the end-of-fiscal-year madness that peaks around this time. In this installment, we’re going to start making it self-aware, or, at the very least, infrastructure-aware, which is the only real way to do truly flexible cloud solutions.

Rui Carmo
June 14^th 2019, at dawn · 1 min read

iPadOS: A New Path Forward? ※

Having read about (and watched videos of) iPadOS, I still get the feeling that this is much ado about a few little tweaks (again, Apple sweating out the details and doing incremental improvements) rather than an actual breakthrough.

I think the main reason for that is that I have a profoundly different take on what “work” means than Federico–like one of my friends said the other day, there is a lot more to the “work” that we do than, say, wrangling Markdown documents, and to this day there is, for instance, no generic web development story for the iPad (very few scripting languages, no way to run anything “normal” locally, etc.), nor a full featured “knowledge worker” setup (you can’t use most professional Office features locally on an iPad, and even corporate e-mail and calendaring is still a pain).

All we really have are cute workarounds, and excellent (but often short-lived) third-party apps that fill some gaps for some of the people, some of the time.

It’s a new start, yes, but still a way off from the status quo.

Rui Carmo
June 9^th 2019, at dinnertime · 4 min read

Catching Up

A great deal has happened this week, which kicked off with what was likely the most eventful Apple WWDC keynote in recent years. I have had little to no time to spend writing my thoughts about it, but an extended weekend is just the ticket for fixing that (as well as posting a few updates on multi-arch Docker images and my upcoming migration away from Dropbox).

Rui Carmo
June 3^rd 2019, at dinnertime · 1 min read

iPadOS ※

This is pretty much all I ever wanted, including native mouse support (as an Accessibility option, and apparently limited to USB only for now) and SMB file access.

Amazingly, my iPad mini 4 is still supported, which is an extra nice touch.

Rui Carmo
May 29^th 2019, in the evening · 1 min read

$99 Is Not Nothing ※

I honestly found Apple’s wording to be dishonest, period.

The $99 developer tax is the sole reason I only developed mobile apps for Android even though I use Apple devices first and foremost–not because I can’t afford it, but because I find a lot of it purely insulting (the limitations in sideloads, the hassle of having to rebuild your personal apps periodically, and, of course, the “added value” of the largely inhospitable developer documentation).

My kids write iOS apps in Pythonista, Scriptable and Swift Playgrounds and the eldest actually writes Python with Cocoa bindings, but helping him evolve beyond that and setting up a “family” developer account seems like a first world problem I don’t want to have, especially if I have to pay $99 for any of it.

Honestly, I don’t think the fee is even a good deterrent against junk apps, since the App Store is already full of them and the app review process (which is a legend unto itself) seems wide off the mark there.

But I would love for the developer program to be recognizably worth anything at this point. I just don’t see the incentive for hobbyists to develop for iOS (or the Mac), and we pay enough for the privilege of using the devices, with all the compromises inherent to iOS at this point.

Why keep those barriers? And, more to the point, why lie about them?

Rui Carmo
May 24^th 2019, at breakfast

Pebbles

A pond around a wooden deck with an adjoing garden — A quiet moment before a team off-site.

Rui Carmo
May 22^nd 2019, at dawn · 1 min read

Apple tweaks its troubled MacBook keyboard design yet again ※

I wish they’d stop futzing about and just redesigned the damn thing from the ground up. Everyone I know (except MacBook 12” owners) couldn’t care less about thinness, and most hate the TouchBar.

I’m also quite amused at the breadth of the keyboard replacement program. Living in a country that, to this day, still lacks an official Apple Store and where support centers (even if competent) don’t provide anywhere near the same turnaround times as in first world countries, I don’t find it the least bit reassuring.

More to the point, every MacBook I’ve touched since 2016 (including my own from that year, which I won’t consider replacing until the keyboards are fundamentally redesigned) has an absolutely lousy feel and is noisy, which is weird considering the Bluetooth Magic Keyboard is actually pretty good.

And since I use Surface devices every day, I have ample proof that you can, in fact, build much more reliable, thin and quiet keyboards. With an Esc key.

Rui Carmo
May 21^st 2019, in the evening · 1 min read

Free Wolfram Engine for Developers ※

Well, this is a surprise.

The licensing terms are predictably restrictive and the licensing process is anachronistic at best (I was going to write “medieval”, but there are no carrier pigeons involved).

I fully intend to give this a whirl and see if I can tie it in to some of my personal stuff (I have Mathematica installed on my lab Raspberry Pi and fiddle with it, but being unable to tie it to APIs and re-use it somehow has severely curtailed my explorations).

Rui Carmo
May 21^st 2019, at late afternoon · 1 min read

Beyond the Tablet: Seven Years of iPad as My Main Computer ※

I’m largely on the same boat – I’m actually typing, capturing and posting this from my iPad mini 4, and I still rate it as my “most personal computer” and the one I rely on for everything except development and cloud work (although I keep trying to make do on it).

For that, alas (which is a very big part of my life), remoting through various means and Safari for iOS (which is a pain to use with any management portal, on any cloud) are simply not good enough yet, and I’ve been eyeing the Surface Go enviously, because it is about the same price and lets me run Docker and everything I need without serious compromises…

That is Apple’s Achilles heel, and even though I fully get that they prioritize creative professionals, I wonder how big (and influential) a market they are missing out on.

I just hope they eventually do justice to the iPad hardware with a powerful enough rendition of iOS—right now, it’s just too limited to meet expectations—and not just mine.

Rui Carmo
May 21^st 2019, at dawn · 1 min read

Huawei’s phone business would be decimated without Google’s Android ※

This has a lot of potential to: a) escalate quickly and b) break a lot of things in the cellphone industry.

Having been keeping track of the core network equipment controversy, there are a lot of people with vested interests on both sides of the fence, and politics is only going to make things uglier.

Rui Carmo
May 18^th 2019, in the evening · 3 min read

Five Less Than Kubernetes, But More Fun

Breaking stuff can be relaxing, and that’s what I’ve been doing this Saturday. And for the past month, really. Ever since k3s came out, I’ve been relishing having a minimal Kubernetes distribution whose internals I can tinker with trivially on ARM devices.

Rui Carmo
May 15^th 2019, at lunchtime

Zebra Event Horizon

the inner courtyard of the EDP building, with its characteristic slats and shade patterns — A unique perspective at the entrance of EDP's new HQ building, just after lunch

Rui Carmo
May 11^th 2019, in the evening · 8 min read

The Surface Laptop

With Build 2019 come and gone, and even though I’m not really the target of most of the announcements and/or see them as logical consequences of the path Microsoft is currently taking, I thought it was time to dust off some notes I’ve left lingering around and never got around to post about something else – the Surface Laptop. But first, a little perspective.