The datacentre-in-a-box for high-performance-computing and cloud software development, testing, and education.

Circumference is a miniaturised datacentre-in-a-box, complete with power distribution and sequencing, instrumentation, cooling, networking and remote console. It is intended for use as a lab platform to support cloud and HPC (High-Performance Computing) software development, testing, and education. Available in 8+1 (C25) and 32+1 (C100) node configurations, Circumference is based around the Raspberry Pi and UDOO x86 platforms, with custom electronics for power distribution, instrumentation and control, and status indication.

Each Raspberry Pi compute node has its own dedicated switch-mode power supply and instrumentation channel. One remote serial console is provided per eight nodes. An UDOO x86 is employed as a front-end processor (FEP) and has software control of power, instrumentation and console routing. The FEP is also used to run an e.g. Kubernetes or MPI master configuration, and in addition may be used to provide network file system and boot services.

Simple to use command line utilities and a Python API are provided for cluster control and energy use logging. The API may be used for such purposes as automating start-up and facilitating integration with configuration tooling, along with scripting compute node and Ethernet switch power control, in order to simulate failure for automated distributed systems testing.


  • 8x / 32x Raspberry Pi compute nodes (total of 128x 64-bit 1.4GHz cores max)
  • 9x / 36x software controlled switch-mode power supplies
  • Instrumentation:
    • 8x / 32x compute node energy
    • 2x / 8x supply voltage
    • 2x / 8x temperature
  • 8x / 50x gigabit Ethernet switch ports
  • 1x / 4x USB UART (multiplexed x8 for console)
  • 1x / 4x software controlled fans
  • 2x / 8x software controlled auxiliary power ports
  • Quad-core Intel Pentium N3710 2.56 GHZ (FEP) with 3x gigabit Ethernet
  • C100 (32+1) node configuration only:
    • 32x LED compute node power indicators
    • 6x LED matrix displays for status

Circumference is currently crowdfunding on Crowd Supply and with limited Early Bird and Early Access C25 (8+1 node) units available.