A $128, Mini-ITX based “Turing Pi Clusterboard” lets you combine 7x GbE-connected Raspberry Pi Compute Modules for private cloud applications. Meanwhile, Pimoroni has launched a $49 RPi Cluster HAT v2.3 that supports 4x RPi Zeros.

Cluster products that combine the computing power of multiple Raspberry Pi boards have long been popular for running a wide variety of private server applications, and more recently there’s been a growing emphasis on edge AI. Like many cluster products, including MiniNodes’ 5 Node Raspberry Pi 3 CoM Carrier Board, the new Turing Pi Clusterboard connects Raspberry Pi Compute Modules — seven of them compared to five on the MiniNodes board — via Ethernet. Meanwhile, the latest v2.3 version of the Raspberry Pi Cluster HAT connects 4x Raspberry Pi Zero boards mounted to a standard Raspberry Pi via USB Gadget mode.

Turing Pi Clusterboard, front and back
(click images to enlarge)

Cluster users and vendors are hotly anticipating the cluster power of the new quad Cortex-A72 based Raspberry Pi 4. Mythic Beasts’s preliminary, 18x Raspberry Pi 4 equipped rig is running the RPi 4 launch page, and PicoCluster promises an RPi 4-based cluster kit by August (see farther below).

 
Turing Pi Clusterboard

Turing Pi’s new cluster platform is available for pre-order for $128 with shipments due sometime in the fall. As reported on Technabob, if you loaded the Turing Pi Clusterboard up with seven $28 Raspberry Pi Compute Module 3 modules, the total price would come to about $325. The Mini-ITX board has a Gigabit Ethernet switch to cluster the CM3 boards. All the modules are powered via a 12V power supply.

Turing Pi Clusterboard with two Raspberry Pi Zero boards (left) and detail view
Source: Technabob (image at left)
(click images to enlarge)

On the coastline you’ll find a GbE port, an HDMI port, and 8x USB ports. There’s also an audio jack, dual MIPI-CSI connectors and a MIPI-DSI interface. Each of the seven cluster slots has its own 40-pin GPIO and its own microSD slot. There appears to be an option to replace these with eMMC storage.

The Turing Pi Cluster is designed for private cloud applications that run container software like Kubernetes and Docker. The product also supports machine learning platforms like TensorFlow and Caffe, and there’s support for Mxnet, the OPENFAAS serverless stack, and Jupyter Notebook.

 
Raspberry Pi Cluster HAT v2.3

HAT-masters Pimoroni, which recently brought us the Enviro+ pHAT air quality detector, have released a new v2.3 version of Chris Burton’s Raspberry Pi Cluster HAT selling for $49. The HAT is designed for “teaching, testing or simulating small scale clusters.”

Cluster HAT v2.3 with (left) and without Raspberry Pi 3 SBC
(click images to enlarge)

It’s unclear what’s new compared to previous Cluster HAT models such as the v2.0. As reported on NotebookCheck, the Cluster HAT v2.3 can cluster up to four Raspberry Pi Zero 1.2 or 1.2 boards, as well as Zero W SBCs, on a Raspberry Pi A+/B+/2/3 board. The system controls the board via “Controller Pi” GPIO and communicates via a micro-USB port to one of the RPi host board’s USB ports using an onboard 4-port USB 2.0 hub. The HAT is configured with USB Gadget mode to communicate either via Ethernet or serial signals.

The HAT has a 40-pin GPIO header and an FTDI Basic connector for Controller Serial Console. Three cluster setup modes are available. Pimoroni also notes that “Controller Pi can be rebooted without interrupting power to Pi Zeros.”

NotebookCheck suggests that it might be possible to use the Raspberry Pi 4 as a host, but that you would need a higher-amp power supply. Pimoroni recommends a 2.5A supply for the RPi 3 and 2A for the others. You will also need to buy a microSD card for each Zero with a minimum of 8GB.

 
18-node Raspberry Pi 4 cluster debuts on RaspberyPi.org

In a proof of concept collaboration with RaspberryPi.org, Mythic Beasts developed a cluster of 18 Raspberry Pi 4 SBCs. As reported by ArsTechnica, the experimental cluster was deployed to run WordPress on RaspberryPi.org’s RPi 4 launch page. Once the new Raspbian Buster distribution adds netboot support, Mythic Beasts plan to build a new RPi 4-based version of its much larger clusters. Customers will pay a bit more for the RPi 4-driven version of its Pi Cloud subscription service.

Mythic Beasts proof-of-concept cluster platform with 18 Raspberry Pi 4 SBCs
(click image to enlarge)

Mythic Beasts’ benchmarks showed a roughly 2.5x performance boost for the Raspberry Pi 4 compared to the RPi 3B+. One challenge was dealing with the RPi 4’s higher power consumption. Mythic Beasts says the board has slightly higher idle power draw (3W) and much higher peak draw of 7W, up from 5W on the RPi 3B+. (A newly released VL805 firmware build for the Raspberry Pi USB3 host adapter “should save about 300mW and help the Pi4 to run cooler, which in turn improves performance in compute-intensive tasks,” says RaspberryPi.org.)


PicoCluster Pico 5H for Raspberry Pi 3 clusters

In other cluster news, PicoCluster, which sells products such as the $169 Pico 5 Raspberry Pi says it will launch a Raspberry Pi 4 version of its high-power H Pico Cluster models in August. The current Pico 5H model shown above has an 8-port GbE switch, an internal 50W power supply, and a fan for $259.

 
Further information

The Turing Pi Cluster is available for pre-order for $128 with shipments due in autumn. More information may be found on Turing Pi’s Turing Pi Cluster product page.

SB Components is selling Pimoroni’s Raspberry Pi Cluster HAT v2.3 for a discounted $49. It’s currently out of stock on Pimoroni’s Cluster HAT v2.3 shopping page. More information may be found on the Cluster HAT website.