The Official Raspberry Pi Projects Book, Volume 5

The Official Raspberry Pi Projects Book Volume 5Raspberry Pi Press has launched the fifth entry in the ongoing Official Raspberry Pi Projects Book series, a family of bookazine-style publications gathering hands-on content previously published in The MagPi Magazine – and, as usual, my content is included.

The Official Raspberry Pi Projects Book Volume 5 is the first volume to be published since the introduction of the Raspberry Pi 4 family – the first in a new generation of single-board computers which brings with it a considerably more powerful processor, the first new graphics processor in Raspberry Pi history, two high-speed USB 3.0 ports, true gigabit-capable Ethernet, and dual-4k display compatibility.

While the bulk of the projects in the book are suitable for any model of Raspberry Pi, there’s some Raspberry Pi 4 exclusive stuff too – in particular my detailed look at the boards, originally written for the Mag Pi’s launch feature. The first feature in the book, it covers the specifications and features of the new board, a look at its performance in a range of synthetic and real-world workloads and including throughput on both Wi-Fi and Ethernet network connections, and two two-page interview spreads with user experience engineer Simon Long and Raspberry Pi Foundation co-founder Eben Upton on both the Raspberry Pi 4 and the new Raspbian ‘Buster’ operating system launched at the same time.

There’s only one thing missing compared to the original version of the feature: thermal performance, including the high-resolution thermal imagery I take of devices on test. There’s a good reason for that: in the latest issue of The MagPi I provided a twelve-page in-depth investigation into the thermal performance of the Raspberry Pi 4 since its launch to the present day through a string of firmware updates designed to decrease power usage and heat output. This represents a considerably more up-to-date look at the board’s thermal performance than in the original launch feature, and it’s entirely sensible to exclude the original test from its republication.

The book is available to buy now in all good supermarkets, newsagents, and for global delivery from the official website; alternatively, a DRM-free PDF copy can be downloaded free of charge under a Creative Commons licence.

The MagPi, Issue 88

The MagPi Issue 88The latest issue of The MagPi Magazine includes a whopping 12-page feature investigating the thermal performance of the Raspberry Pi 4 Model B single-board computer as it is affected by a series of firmware updates released since its launch earlier this year.

When I reviewed the Raspberry Pi 4 at launch, I highlighted its dramatically increased power draw and heat output compared with its predecessor the Raspberry Pi 3 Model B+. In the months since, the Raspberry Pi Foundation has been working to address the issue through a series of firmware updates – and, with assistance from Eben Upton and Tim Gover, my feature runs through each release and sees what difference it actually makes.

For the feature, I had to develop a method of benchmarking the Raspberry Pi. Power draw was relatively straightforward: the built-in current meter in a bench-top power supply is used to measure the minimal draw at idle and peak draw at load. For thermal performance, I wrote a custom benchmark which uses two open-source utilities – glxgears and stress-ng – to place a heavy load on both the CPU and the GPU while measuring the resulting temperature rise and the speed of the CPU, which throttles at 80°C to protect the silicon.

These measurements provided a graph of temperature rise and fall, the latter thanks to a five-minute cool-down period built into the benchmark, but for a more visual approach I also took thermal imagery of the board at idle and load to demonstrate which components are responsible for the heat output and better highlight the improvements made at each firmware revision. This was no small undertaking: the benchmarking and thermal imagery was completed for five firmware revisions, the last of which was not publicly available at the time of testing, plus a baseline Raspberry Pi 3B+ for comparison.

The feature also takes a look at a real-world workload, in which temperature and clock speed is measured while a four-worker compile of the Linux kernel is carried out. This revealed something which may come as a surprise to critics of the board: Using the latest firmware, the Raspberry Pi 4 did not throttle at all during the compilation – something that can’t be said for the Raspberry Pi 3B+, which throttled to 1.2GHz from 1.4GHz almost immediately. For the final bit of testing, there’s even a comparison of the Raspberry Pi 4 running sat flat on a desk and balanced vertically – at Upton’s suggestion – with a resulting dramatic impact on the throttle point and operating temperature.

Finally, firmware developer Tim Gover was kind enough to answer my questions on what the Raspberry Pi 4 firmware actually does, how it is developed, and how it can have such a dramatic impact on power usage – along with the confirmation that USB mass-storage booting and IPv6 network booting are on the to-do list for future releases.

The full feature, and plenty more beside, can be found at your local newsagent, supermarket, or downloaded at no cost in digital form under a Creative Commons licence from the official website.

The MagPi, Issue 83

The MagPi Issue 83This week saw the release of the Raspberry Pi 4, first in a new generation of single-board computers from the not-for-profit Raspberry Pi Foundation. As is usual for the launches, I was approached by The MagPi Magazine – the Foundation’s official publication – to prepare coverage for the launch, including interviews, imagery, and a wealth of benchmarks.

My coverage for the magazine, spread across a whopping 12 pages, begins with a high-resolution hero shot of the board with macro-image call-outs for its key features and components – including the new USB Type-C power connector, BCM2711B0 system-on-chip, and shiny dual-micro-HDMI video outputs capable of driving high-resolution 4K displays.

Next, there’s an interview with Foundation co-founder Eben Upton covering everything from the reason the board is available now when a 2020 launch had previously been suggested, how it can potentially replace a desktop PC in a range of environments, backwards compatibility with the existing Raspberry Pi ecosystem, and a hidden Easter Egg on the PCB – only accessible to those brave or foolhardy enough to unsolder the USB connector.

The benchmarking section, spread across four pages, marks a departure from previous launches: this time around I pulled the focus away from synthetic benchmarks, though the classic Linpack still makes an appearance if only to demonstrate how the Arm processors’ NEON extensions can dramatically improve performance, in favour of a variety of real-world workloads: image editing with the GIMP, file compression with bzip2 and lbzip2, browser performance in Chromium, and gaming performance with OpenArena, alongside USB, Ethernet, and Wi-Fi throughputs. In all cases, the workloads are entirely reproducible: all packages used for the real-world workloads are available at launch in the Raspbian Buster software repositories. If four pages isn’t enough, additional benchmarks are available on my Medium post.

As usual, the benchmarking also includes a thermal analysis: images of the Raspberry Pi 4 and its immediate predecessor the Raspberry Pi 3 Model B+ were taken after a ten-minute CPU-heavy workload using a Flir thermal imaging camera, the data processed to a fixed temperature scale of 22-80°C to avoid noise from ambient surfaces, then overlaid on an edge-enhanced high-resolution visible-light image of their respective boards using a high-contrast rainbow colour palette. These images represent a fair amount of work, but there’s no better way to see both how hot the Pis get under continuous load and which components are responsible for that heat – not to mention how effective the design is at bleeding the heat off through the PCB, something with which the older Raspberry Pi models with plastic-encased chips have struggled.

Finally, the piece closes with a two-page interview with Simon Long on the new Raspbian ‘Buster’ operating system – launching ahead of the upstream Debian 10 ‘Buster’ release, interestingly – and its revised, flatter user interface. While much of the under-the-hood work for Buster was to get it ready for the Raspberry Pi 4 – previous Raspbian releases won’t work on the new board – it’s also available for older Raspberry Pi models, and comes with some convincing reasons to upgrade along with a handful of software compatibility issues that offer a reason to hang fire.

As always, The MagPi Issue 83 is available to buy in print format from all good newsagents, supermarkets, and book sellers; a free digital copy, released under the Creative Commons Attribution-ShareAlike-NoCommercial licence, is also available from the official website.

The MagPi, Issue 76

The MagPi Issue 76There’s no missing my contribution to this month’s The MagPi: it’s plastered all over the cover. The launch of the Raspberry Pi 3 Model A+ ends a four-year absence of the compact form factor from the Raspberry Pi line-up, and there’s no better way to celebrate its launch than with a massive cover feature.

The spread begins with a two-page introduction dominated by imagery of the board, before moving on to a plan view which calls out the individual components that make up the board – including the single USB port, BCM2387B0 system-on-chip (SoC), and the radio which, for the first time in a Model A variant, adds WiFi networking and Bluetooth connectivity. Each part includes macro photography, all taken in my in-house studio.

The next section of the feature runs through a series of benchmarks which, in-keeping with previous launches I’ve covered, compares the Pi 3A+ with other mainstream Pi models going all the way back to the original Raspberry Pi Model B. The feature also includes a look at the size and weight, the first time I’ve used that particular metric, along with comparative thermal imagery showing how the smaller surface area of the PCB copes with running the same high-performance processor as the larger Pi 3B+ – again, all captured in-house.

Finally, the cover feature closes with a two-way interview I conducted with project co-founder Eben Upton and principal hardware engineer Roger Thornton. In it, Eben confirms that the Pi 3A+ represents “tidying up ‘classic’ Raspberry Pi,” and that the Raspberry Pi 4 – still very much on the drawing board – will launch a whole new era for the low-cost single-board computer family.

The launch issue is available now from your nearest newsagent or supermarket in print, or can be downloaded free of charge under a Creative Commons licence from the official website.

Benchmarking the Raspberry Pi 3 B+

Raspberry Pi 3 B+

The launch of the shiny new Raspberry Pi 3 B+ offers a chance to revisit the entire history of the Pi family, benchmarking each device in turn from the original Raspberry Pi Model B launch board with its somewhat limited 256MB of RAM right through to the shiniest and newest board. This post collates the results from a range of different benchmarks, demonstrating how the power of the Pi has changed over the years.

If attempting to replicate the results yourself, there is one key fact to note: the Raspberry Pi has enjoyed somewhere in the range of a 30 percent performance uplift in the last couple of years through software and firmware optimisation alone; comparing the same benchmark run on a Pi using the latest Raspbian operating system today with results gathered a year or more ago will give a false reading, which is why all these results have been gathered using the same firmware and software revision.

 

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Custom PC, Issue 152

Custom PC Issue 152In this month’s Hobby Tech column I review the Proster VC99 multimeter, the Intel/Arduino Genuino 101 microcontroller development board, and discuss the challenges in developing meaningful benchmarks for testing devices where memory is measured in kilobytes.

Unusually for a hardware review, the multimeter was actually a personal purchase: I’d been using a Maplin-branded multimeter for quite some time, but the low cost and seemingly broad features of the Proster VC99 – also known as the Vichy 99, and sold under a variety of badges – convinced me it was time for an upgrade. While doing so cost me a back-lit display, I gained a variety of functions from frequency counting up to a neat analogue bar-graph on the display for seeing spikes and dips that would otherwise be lost on a numerical output.

The frequency counter came in particularly handy for my Genuino 101 review: writing a simple Arduino Sketch which does nothing more than toggle a pin on and off as fast as possible, I was able to read how quickly that happened to give me an idea of the IO performance of the Genuino compared with other Arduino boards I have lying around. Coupled with a look at the Intel Curie module which powers the device, providing Bluetooth connectivity and an integrated accelerometer, that’s enough for a solid review.

I don’t want to do solid reviews, though, I want to do great reviews, so the last page of this month’s five-page spread looks at how I benchmarked the compute performance of the Genuino 101 against an Arduino Nano for a direct, head-to-head comparison. It’s not as easy as it sounds: with mere kilobytes of memory, it’s not like I could just install PC Mark and be done with it. Interested parties will find a detailed explanation of how I went about modifying the traditional Dhrystone and Whetstone benchmarks to run on both devices, including trimming things to fit into the Arduino Nano’s tiny memory allowance, and how to interpret the results.

All this, plus stuff by people who aren’t me, is available at your nearest supermarket, newsagent, or from the comfort of your home via digital distribution services including Zinio.

The MagPi, Issue 43

The MagPi Issue 43It’s a special week for the Raspberry Pi Foundation: it’s celebrating its fourth birthday with the launch of the new Raspberry Pi 3. It’s a special day for me, too: the latest MagPi magazine boasts a total of thirteen pages of my content, including the cover splash: a detailed and thorough look at the new model.

Boasting on-board Wi-Fi (a community request since the original model launched four years ago), Bluetooth 4.1, Bluetooth Low Energy, and a faster 64-bit ARMv8 processor, the new Pi 3 is a bit of a beast. My cover feature for the magazine begins with a look at those behind it with a double-page spread featuring interviews with project co-founder Eben Upton and the Foundation’s director of hardware and the man responsible for circuit design James Adams – and a massive thank-you to both for sparing the time to talk to me at one of their busiest ever periods!

The feature then moves on to a look a the board itself, with a hero photo of the board spread across another two pages. Each major feature of the board, from the shiny new 64-bit BCM2837 system-on-chip (SoC) processor to the BCM43438 radio module – which required me to get out the microscope in order to capture its markings – has a call-out with close-up photography and an explanation of how it has changed since the Raspberry Pi 2.

Next up is a benchmark spread, which required me to come up with a detailed suite of tests. After some experimentation, I settled on a selection of classic benchmarks – SysBench CPU in single- and multi-threaded modes, Linpack with and without NEON support, Whetstone, Dhrystone, SysBench memory read and write, Ethernet throughput, Quake III Arena timedemo performance, and power draw at load and idle. As an added bonus, I also came up with a way of measuring general-purpose input-output (GPIO) performance under Python, writing a simple benchmark to toggle a pin on and off as quickly as possible and measuring the speed with a frequency counter connected to the GPIO header.

The next double-page spread looks at helping the reader get started with the new device. I walk readers through modifying an existing Raspbian installation to boot on the Pi 3 by editing config.txt, setting up the Wi-Fi module, enabling true OpenGL acceleration on the graphics processor, and how to write programs to get the best performance on the Pi 3. Sadly, I was unable to explain how to use the Bluetooth 4.1 and Bluetooth Low Energy features, as software support was not available at the time of writing.

The spread then ends with a look at five things you could do with a Pi 3 in order to take advantage of the new features and boosted performance. My work for the magazine continues, though, with a review of the Proster VC99 multimeter and Pimoroni pHAT DAC, before coming to a close with a one-page news piece regarding the production status of the popular Raspberry Pi Zero – helping to explain why it has been so difficult to get hold of and settling concerns that it may be bumped to the back of the production queue now the Pi 3 is out.

All 13 pages of my content, and plenty of other stuff by people who aren’t me, are available from your nearest supermarket or newsagent, or as a free PDF download under a Creative Commons licence from The MagPi’s official website.

Custom PC, Issue 116

Custom PC, Issue 116This month’s Custom PC Magazine is a bumper issue for me: a massive in-depth Raspberry Pi feature is splashed across the cover, for which I provided all but the build-your-own-case section. As usual, the magazine also includes my regular interview column, this time talking to open hardware guru Andrew Back.

First, the Pi material. With the Raspberry Pi having had a phenomenally successful first year, and Custom PC having missed the chance to latch onto that with a cover splash for the launch review, it’s no surprise to see the magazine going all-out to attract Pi fans. Those who pick up the magazine for its Pi-related content are in for a treat, too.

First up is a head-to-head review covering the newly-released Raspberry Pi Model A and the redesigned Raspberry Pi Model B Revision 2. While some differences are obvious – the lack of a second USB port and Ethernet on the Model A, for example – others are less so, and the review hopefully answers the question of whether it’s worth paying the extra £12 to get the Model B over the tempting £18 asking price of the Model A.

The benchmarking continues with a look at how to overclock a Raspberry Pi without voiding your warranty, along with a few tips as to how to push it to ever-faster levels. Using a retail-model Raspberry Pi Model B Revision 2 equipped with a couple of cheap aluminium heatsinks, I was able to push the CPU from 700MHz to 1.1GHz and the GPU to 500MHz – and it made a serious difference in performance, as the benchmark results show.

Next, I walk newcomers to the project through installing the Raspbmc media server software and configuring it to stream HD YouTube content – something you’d think a £30 PC would struggle to do, but that’s certainly not the case. There’s also a look at the Minecraft: Pi Edition release, which provides a hackable and completely free version of Mojang’s popular block-’em-up game with which tinkers can fiddle around.

Finally, there’s a round-up of the four most popular operating systems for the Pi: Raspbian, the Debian-derived Linux distribution chosen as the ‘official’ OS by the Raspberry Pi Foundation; Raspbmc, the media-centric Linux distribution with integrated Xbmc support; RISCOS, by far the fastest OS for the Pi; and FreeBSD, for those who eschew Linux but still want a POSIX-compliant environment.

With the Pi work done, the interview. Andrew Back is one of the brains behind the Open Source Hardware User Group (OSHUG), and recently moved into my (relative) back-yard in Hebden Bridge. He’s a great guy, and always up for a chat – and his knowledge regarding open hardware, a still relatively unknown offshoot of the open source and free software movements, is second to none.

All this, and more by people who are not called Gareth Halfacree, can be yours if you just mosey on down to your local newsagents and pick up Custom PC Issue 116. Alternatively, stay indoors and get a digital copy via Zinio.

Linux User & Developer, Issue 104

This month sees just two pieces of mine in Linux User & Developer magazine: a review of the Efika MX Smarttop and a group test of popular filesystem-level encryption tools.

It’s always fun doing a hardware review for a change, and the Efika test was no exception. Based on an ARM architecture processor and shipping with a cut-down version of Ubuntu, any benchmarking tools need to be compiled from scratch in order to run.

The encryption group test was a departure from my usual fare: because the software on test has an actual, measurable performance impact on the host system, it’s possible to get an objective – rather than subjective – idea of which is ‘best.’

Building a custom benchmarking script, I created a small volume on a virtual host which was then encrypted using each of the filesystem encryption utilities. Files were then copied to and from the volume – with both sparse and dense files in small and large chunks chosen – with each transaction rated in terms of transfer speed and CPU load.

Between tests, the virtual machine was rolled back to an earlier snapshot – one of the major reasons I do this kind of testing within VirtualBox, rather than on a physical host – to ensure that file caching, fragmentation and the like couldn’t skew the results.

More information is available on the Linux User & Developer website.