Progress as of 7th of June

This is where Marks Rpi Cluster was on the 7th of June. A total credit of 7.925,948 with an average of 3,613 credits. Not as much as 50 days ago but its starting to climb back up.

Currently the cluster has two Pi4 4GB models doing Rosetta and 10 Pi3 doing Einstein BRP4 work.


Pi4 news
Following the announcement of the 8GB Pi4 model B, I had a look around at the couple of suppliers I get them from. Both were out of stock. Element14 (who are one of the worldwide distributors) has them back ordered into August and the other supplier had a limit of 1 per customer with stock arriving in a week. Given the memory some of the Rosetta work units use, the Pi4 4GB can only run 3 tasks at a time so the 8GB model is the one to get.

I haven't tried the new Raspberry Pi OS (64 bit) yet, although one of the users at Einstein had success running Rosetta work on a Pi4 8GB. His Pi appears to be running Debian buster with a 5.4 kernel. I would have to take one of my current Pi4's out of service while I experiment with it, which I don't want to do at the moment. It is more important that they run Rosetta work.

Update:
Ordered one Pi4 8GB, power supply and a case.

8GB Pi 4 model B announced

The Raspberry Pi foundation announced the availability of the 8GB Pi 4 model B. They promptly all sold out. To quote part of their official blog post:

"The BCM2711 chip that we use on Raspberry Pi 4 can address up to 16GB of LPDDR4 SDRAM, so the real barrier to our offering a larger-memory variant was the lack of an 8GB LPDDR4 package. These didn’t exist (at least in a form that we could address) in 2019, but happily our partners at Micron stepped up earlier this year with a suitable part. And so, today, we’re delighted to announce the immediate availability of the 8GB Raspberry Pi 4, priced at just $75."

I would assume the price is in US dollars. It would certainly help when running Rosetta tasks where my 4GB Pi's don't have enough free memory to run 4 tasks at a time.

They also mentioned that they are looking at a Debian ARM64 operating system (sometimes referred to as aarch64). Debian already has an ARM64 build but it isn't customized for the Pi. Raspbian can be put into 64 bit mode but suffers because all the other apps and libraries are still 32 bit. We'll have to see how long before the 64 bit Debian becomes available. They didn't want to refer to it as Raspbian because that is the 32 bit operating system.

Onto cluster news now, and well, there isn't much to report. MarksRpiCluster is running the two Pi4 4GB nodes on Rosetta and another six Pi3;s are on Einstein. Speaking of Einstein they stopped their work splitter yesterday so the six Pi3's all ran out of work. This is the second time in a month they have run out of work. I have increased the BOINC cache a little in the hope of keeping enough work on each one so they can last a day.

2nd of May

This week the 3rd Pimoroni fan shim seized up. That is 3 out of 3 failed after a few months of running. I've done a temporary arrangement of suspending a Noctua 40MM fan over the top of the SoC and plugged it into the GPIO pins for power in order to get the Pi4 going.


BOINC project news
Last week the Einstein@home ran out of BRP4 work so the Pi3's all had a holiday. The project have since provided new work. They normally have plenty of work for the slower devices like the Pi.

Asteroids@home released new apps. This included a new 102.13 app for the Pi. I don't recommend you use it. The 4 work units I downloaded ran for over 35 hours. I've since removed the project from the Pi that I tried it on.

Rosetta@home also released a 1.20 app for all platforms. A long asked for improvement with this app is it unpacks its databases into the project directory rather than slot directory. This allows them to be shared with other tasks, saves a lot of  writes to the SD card (the databases are up to 1.1GB) and reduces the number of copies to one. Previously it used to unpack them into the slot directory at the start of each task and then delete them when the task finished.

11th of April

Marks Rpi Cluster currently consists of:
2 x Pi4 model B (4GB)
2 x Pi4 model B (2GB)
14 x Pi3 model B+
6 x Pi3 model B

The two Pi4 4GB are concentrating on Rosetta work. The two Pi4 2GB are support nodes. The Pi3's are concentrating on Einstein work.


Cooling
The two Pi4 4GB models were using Pimorni fan shims for cooling but another one seized up today. I had to use a Noctua 40MM fan in its place. The Pimoroni fans only seem to last about 3 to 4 months of constant running. I have already replaced one under warranty.


Power
I purchased a number of Mean Well power supplies to run the Pi4's. I will be replacing the Pi3's with Pi4's. This power supply is the LRS-75-5 model which provides 5 volts at 14 amps which should be more than enough to run 4 x Pi4 nodes.

As you can see they are a bare-bones power supply with no wiring. I will probably have the cases 3D printed as there is nothing available that would suit them.


Rosetta tips
If you want to help with Covid-19 research and are familiar with BOINC and have a Pi4 I would encourage you to run the Rosetta@home project. See my previous blog post on how to get Raspbian into aarch64 mode and BOINC requesting aarch64 work.

Tasks need up to 1.3GB of memory (it depends on the work unit) so a Pi4 2GB could run one and a Pi4 4GB could run 3 at a time. Unfortunately the Pi3's and Pi4 1GB don't have enough memory.

The tasks have a 3 day deadline, so run a small cache setting. The project recommend 1 day, however I run mine with 0.3 days. Tasks have a fixed run time which defaults to 8 hours.

Each running task can use up to 2GB of disk space, so use a 8GB micro SD card or larger. I'm using 16GB micro SD cards. Change the BOINC setting to allow up to 6GB of disk space to be used.

To reduce the writes to the micro SD card I recommend setting the BOINC checkpoint interval to 300 or 600 seconds. Mine are set to 600 seconds