Limits imposed by 1GB RAM

My HA use case merely connects six radio thermostat devices for internet access. HA series up the status of the thermostats and can temporarily change the target temperature.

The HA container runs on a PC / Ubuntu, however, I would like to use the PC for other tasks if I can run HA OS on a raspberry pi 3B+ (1GB RAM).

If I downsize to a 3B+ (1GB RAM): what limitations are imposed by a meager 1GB RAM?

If the HA OS is installed on the rPi 3B+, is there a documented procedure to migrate the PC’s HA configuration to the 3B+. Ideally it would be as simple as copying an XML file.

First, I don’t run containers or VMs. My Home Assistant is the native X-86 on an Intel NUC all by itself. But generally, you do a complete snapshot (backup), then install Home Assistant on the new hardware then do a restore. I’ve done this twice. Once when migrating from a Raspberry Pi and again when migrating to a different Intel NUC. (From an i7 to an i3).

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Thank you for the reply: I think you are indicating that you have migrated from an rPi to a NUC: a backup and restore is independent of the CPU? I am going the opposite direction (LOL).

Is the rPi HA-OS the leanest OS (so as to use scare 1GB RAM efficiently)?

I would think so. But it only costs some time to try it.

I ran my HA instance on a 3b+/1gb Pi for a year without issues. Esphome, lights, thermostats, mqtt, zigbee, …

I dont see any blockers for your scenario from a performance/ram side.


My parents have a Pi 3B+ and zero problem: Mqtt, Adguard, Esphome, Samba, about 20 devices…

If you don’t need a lot of addons it should works fine.


Yes it’s hardware agnostic. Really cool huh?

HAOS is not the ‘leanest’ but by far the easiest. It’ll run fine on the pi3 in a very small load and if you find it isn’t performant backup and slam it back down on a Pi4, or a green or a Nuc or a VM Inside Proxmox.

Edit:o have what you would call a VERY complex install and I’ve been on a Pi4 for years - just now looking at my next platform to grow into. Probably a NUC or other mini PC.

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Very cool! How much RAM is in your PI4?

Is there some canonical metric for mapping total functionality to RAM? e.g. Sometimes software is measured in “function points”, however, it is mapped to schedule / cost and not RAM.

I have stoodup the rPi 3B+ and it seems to be effective: I would like it to enable remote access to the thermostat and serve as an SSH server so I can tunnel into the LAN remotely.

8gb on the Pi.

I use Nabu Casa for mine as I need it (I also like supporting thier work)

SSD, USB stick or SD card?

Never an SD card. Sds are not designed for database writes. (which is exactly what recorder is in HA.

Argon one case, 250GB M.2 SSD (i got a deal on two identical ones and keep the second as a spare)