Starting with Pi4 model B

In the last fortnight I ordered another two Pi4 model B's. The 2GB version this time. I already had two of the 4GB versions, one as a proxy server and one as a storage server. I swapped them around so they became 2GB devices, they don't need large amounts of memory.

I used a different supplier this time as they had the Pimoroni fan shim. My regular supplier (Element 14) doesn't seem to carry the fan shim. I have put one on a 4GB Pi4 compute node. While crunching I am seeing temps of 50-51 degrees C on the Pi4B with the fan shim and the top of the case off. The room temperature is 28 degrees C.

The idea is to run a few Einstein BRP4 work units through using armhf (32 bit mode) to get timings and then I will switch it to 64 bit mode and try it again. Current work units, running 4 at a time under the armhf architecture, are estimated around 7 hours on the Pi4. It hasn't finished yet. The Pi3B+'s have been taking a bit over 11 hours and the Pi3B's have been around 11 and 1/2 hours.

There isn't a project supplied arm64 app but there is an optimised arm64 app available. We're hoping to get the Einstein project to accept the arm64 app seeing as they don't currently have one.

Another reason for switching to the arm64 (otherwise known as aarch64) architecture it that there is an experimental Einstein FGRP app for it. It needs around 1GB of memory per work unit so a 4GB Pi4 will be required to run it on all four cores.