July 2026 update

I assembled the stackable Pi case, put the 4 loose Pi5's into it and used zip ties to hold the 80mm Noctua fan to its side. Airflow is better than the other stackable case so I'll need to swap the other case fan out for a Noctua when I get time.

I also rearranged the support nodes so there is one less with the proxy server now also a storage node (it had a USB SSD anyway). This brings Mark Rpi Cluster to:

24 x Pi4 (8GB) as compute nodes
8 x Pi5 (4GB) as compute nodes
2 x Pi5 (4GB) as support nodes

All the Pi4's are running Einstein@home BRP4 work. The Pi5's are also running Einstein@home but have Asteroids@home as a backup project so when they can't get Einstein work they'll run it. One of the Pi5's picked up some Asteroids work which it has now decided to swap out so it can run Einstein again, hopefully it will finish the Asteroids work soon.

 

19 July update
The four older Pi5 passed 1 million credits each for Einstein this week. I have put these four into run-off mode in order to change the fan on its stackable case. It will take a couple of hours to finish their current work.

The newer Pi5's have now got their host average for Einstein up to the older Pi5's which is around 2500 credits. By comparison the oldest Pi4 is on 1.718 million credits but it had a couple of years head-start.

 

June 2026 update

In keeping with the hardware updates, Marks Rpi Cluster is also getting some new kit. I have been buying some Pi5 (4GB) but the resellers are limiting them to one per customer so it takes multiple orders. I'm adding another 4 of them to the cluster. I have ordered one of those stackable things you put them in made from clear acrylic and some metal posts, waiting for it to come from China.

The Pi4's continue processing Einstein BRP4 work. The Pi5's are also doing Einstein BRP4 work but have done a few Asteroids tasks in between. The Pi5's are up to 900M credits for Einstein. It will take them a while to beat the Pi4's which have been running longer. 

 

27th of June update

The stackable Pi Case arrived. All 4 Pi5's arrived and are up and running. The 4 new Pi5's are sitting loose on a table top at the moment. That brings the cluster up to 8 Pi5's for compute. I need to assemble the case which has no instructions so its going to be trial and error.

I had issues with the new Pi5's losing their network connection when plugged into the same switches that the EC12's use. Each EC12 has 12 x Pi4's plugged into a 16 port switch. Each 16 port switch is in turn plugged directly into the router. I dug out an old 5 port gigabit switch, plugged it into a different switch and the 4 new Pi's are connected to it which seems to have resolved the connectivity issue. 

I got a couple of Noctua 80mm 5v fans. I'll attach one to the side so it draws air across the Pis. The Pi5's all have the official active cooling fan/heatsink so its there to help them. There isn't much space between each layer. The other case I have is using a slim 80x10mm 5v fan which doesn't move much air. The Noctua fans are 80x25mm and have a higher airflow. The Noctua fans come with a USB type A adapter cable so I can plug them into one of the Pi5's for power.

 

March 2026 update

Currently the 4 x Pi5 nodes are running Einstein.

There was a debian point release so I need to go through each of the Pi4's and update them before I can bring them online. 

Purchasing the Sandisk High Endurance micro SD cards (yes I use them for the Pi's primary storage) I can no longer get the 32GB versions. It seems Sandisk have moved to 64GB as the smallest size these days with a price increase.

Rpi Imager 2 and Dec 2025 Raspberry Pi OS

I took the opportunity over the Christmas break to upgrade one of the Edge Cluster 12's to Raspberry Pi OS based upon Debian Trixie. They had been running the Debian Bookworm version of Raspberry Pi OS. Unfortunately I ran across a couple of problems.

There is a "design feature" with the Raspberry Pi Imager v2 where the Raspberry Pi foundation have removed the ability to customize images, so one cannot set the host name, user name, password or other settings. Well technically you can but only by writing JSON code for the Imager. I strongly recommend you keep Imager 1.9 if you need this ability.

Coupled with being unable to customize the image the Dec 2025 release of Raspberry Pi OS has changed some boot parameters so one cannot (even using Imager 1.9) customize the image.

For more information you can read the bug report on Github HERE where the developer has closed the bug as "won't fix".

Despite the above I managed (after a lot of attempts) to get 12 new micro SD cards imaged and replaced the existing ones in one of the Edge Cluster 12's. Those 12 Pi4's have been running Einstein@home work since. The Pi5's were upgraded soon after the Raspberry Pi OS based on Debian Trixie became available. That leaves me with another Edge Cluster 12 (ie 12 x Pi4s) to upgrade.

My current install process is to use Imager 1.9 and the Oct 2025 release to image the SD card. Once done and the Pi has booted do an "apt update" and "apt upgrade -y" to get it up to date.

 

Running slowly

Hot weather has returned so the farm is working in between.

As well as the weather the Raspberry Pi foundation released Raspberry Pi OS based on Debian Trixie on the 1st of October. I have been updating the support nodes to see how things work out. The only major change is the swap space is now 2GB and they're using zram for swap. I've updated all the Pi5's but have yet to update the Pi4 compute nodes.

Another quirk I found was the "lite" version doesn't include nfs-common so after getting stuck I found out you have to install it before you can use an nfs mounted drive. The full version or Raspberry Pi OS (ie with a desktop) includes nfs-common.

September update

The farm is still running 24/7. We had a few hot days earlier in the week, where I had the farm idle (ie running but not doing any tasks). 

Asteroids@home seems to have disappeared so I removed it from all the Pis.

Debian trixie was released and I am waiting for an updated version of Raspberry Pi OS. I've upgraded all my x86-64 machines.

I purchased more micro SD cards, the Sandisk high endurance ones so I should be ready to replace all of them once Raspberry Pi OS is available. The shop had 256GB cards available but the price was too high and I don't think I need that much disk space. I settled for 32GB cards instead being the cheapest of the high endurance variety. Most of my Pi's have older Sandisk Ultra 16GB cards at the moment which seem to last around a year to 18 months before I have to replace them.

 

Still crunching Aug 2025

Marks Rpi Cluster is continuing to run 24/7 and getting through work. Its doing Einstein. Asteroids still haven't re-applied their Pi optimizations so I am sticking with Einstein for the time being.

 

Rpi OS based on Debian trixie

Debian Trixie is due for release on the 9th of August. Raspberry Pi OS is based on Debian. The Rpi foundation said that they aren't likely to have any major updates until they upgrade to Trixie. Last time Debian updated (approx 2 years ago) there was quite a few months before Raspberry Pi OS caught up so hopefully it won't take too long this time.

Most of my Pi's run headless (no screen and keyboard) and I run the "lite" version which doesn't include a desktop environment so I probably won't see much change, although there are a lot of improvements to apt, the package manager that Debian use.

I will be trying it on a Pi5 first to see what works and what has changed before imaging a bunch of SD cards. To do the EC12's I will have to open up each one to get to the SD card slots on each Pi. I do a clean install from scratch rather than attempting to upgrade from the previous OS. Earlier versions of Rpi OS didn't officially support upgrading the operating system.

 

Still running

The farm is still running and still doing Einstein BRP4 work. I tried the Asteroids@home work but they have a problem with their app missing some optimizations that make them take longer than before and they make the Pi's run hotter. The farm consists of:

2 x Pi5 (4GB) as support nodes.
4 x Pi5 (4GB) as compute nodes.
24 x Pi4 (8GB) as compute nodes.

We're in winter at the moment in Sydney, Australia so the farm is running 24/7 at the moment. The farm is currently on 36,094,879 credits with a recent average of 42,759 credits.

  

As mentioned in previous posts I would like to update the farm to all Pi5 nodes, however the Edge Cluster that I use for the Pi4's doesn't support them. There has been no news from BitScope regarding Pi5 support.

I wouldn't be surprised if there is a Pi6 coming soon as the Raspberry Pi foundation have updated the Compute module 5, Pi500 and Pi5 to all use the BCM2712 as well as releasing a Pi5 with 16GB of memory.

With the fake numa node settings it would appear recent Rpi OS updates have been automatically enabling it. While I tried it on the Pi4's I didn't notice any advantage for them, but it certainly make a difference with the Pi5's.

Updates and remove some firmware

The weather cooled off a bit and its been raining which also helps bring the temperatures down so I had the Pi5's running and fired up half of the Pi4's.

The Pi4's having been off for quite a while needed updating which took a while due to the number of  packages and there was a kernel update.

It seems that even with the Raspberry Pi Lite image they have started bundling GPU firmware. If you use any of these you are probably running the desktop version of Raspberry Pi OS, not the Lite version. I am guessing this is because Jeff Geerling has been working to on getting GPU's running with the Raspberry Pi5.

None of my Pis have a GPU so I remove those packages. You can check on the Debian website what driver is in each package. In a terminal or ssh session type:

sudo apt purge firmware-intel-graphics firmware-marvell-prestera firmware-nvidia-graphics firmware-mediatek firmware-intel-misc firmware-libertas firmware-misc-nonfree

sudo apt-mark hold firmware-intel-graphics firmware-marvell-prestera firmware-nvidia-graphics firmware-mediatek firmware-intel-misc firmware-libertas firmware-misc-nonfree

sudo apt autoremove

While I was at it I also added the fake numa-node changes to improve memory timing. You can find the instructions on the Raspberry Pi forums and it only works for the Pi4 or Pi5. The Pi5's seems to be around 18% faster when running the Einstein BRP4 app. At a rough guess 5% for the Pi4, so not as big an improvement but that is from a small sample.