What's the status of 64- vs 32-bit pioreactor builds?

noahsprent · August 7, 2025, 9:24am

I’ve looked through and seen a couple of references to 64-bit builds in the past, but as far as I can tell the default is still 32-bit. As far as I can see my Pi is running a 64-bit kernel with a 32-bit userland, but I might have diverged from the original image I installed overtime, I haven’t gone too deeply into it. 32-bit is a pretty big limitation for stuff like running ML/AI things, e.g. trying to get Goose CLI to run. I admit that’s pretty niche, but maybe Trixie OS release · Issue #460 · Pioreactor/pioreactor · GitHub is an opportunity to go 64-bit by default? How many people are actually running on low-spec PIs?

Relatedly, doesn’t look like the nightlies are 64-bit? Are there any 64-bit images I can grab to try to test out the goose/LLM/MCP stuff? Would I have to build myself using CustoPiZer?

CamDavidsonPilon · August 7, 2025, 2:47pm

Ah we use to have 64bit builds! But they weren’t used much. The problem is 64bit builds work best on > 1gb RAM RPis, but the popular RPi Zero 2 is only 512mb RAM. TBH I haven’t tried a 64bit build on the Zero 2, so I can’t say what the impact is.

I’ll try to get 64 bit builds back on nightly later today so you can try.

CamDavidsonPilon · August 7, 2025, 5:16pm

There is a 64 bit build available here: Index of /nightly/leader_worker/ :

pioreactor_leader_worker_2025-08-07_64.img.zip

totally untested! It’s also pointed at our develop branch, so there are some experimental features there. You can see our upcoming changes here: pioreactor/CHANGELOG.md at develop · Pioreactor/pioreactor · GitHub

noahsprent · August 7, 2025, 6:21pm

Epic thanks

CamDavidsonPilon · August 8, 2025, 3:01pm

You need to create the models dir: mkdir .pioreactor/models
Need a config change for mcp:

sudo nano /etc/lighttpd/conf-available/50-pioreactorui.conf

add the line:

"^(/mcp/.*)$" => "/main.fcgi$1",

below

"^(/unit_api/.*)$" => "/main.fcgi$1",

So like:

url.rewrite-once = (
 "^(/static($|/.*))$" => "$1",
 "^(/api/.*)$" => "/main.fcgi$1",
 "^(/unit_api/.*)$" => "/main.fcgi$1",
 "^(/mcp/.*)$" => "/main.fcgi$1",
)

noahsprent · August 11, 2025, 12:35am

Nice! Obviously lots to test but working for me Installed goose CLI as well. Running on an 8gb 4b. Only hiccup was that there’s no keyring to store API keys so you have to give them as environment variables to goose. It’s a silent failure though so took a bit to figure out

noahsprent · August 11, 2025, 12:30pm

How does the models thing actually work? I added a file CB01 to the .pioreactor/models folder:

model_name: custom_100ml
model_version: “1.0”
display_name: “Custom 100 mL, v1.0”
reactor_capacity_ml: 100.0
reactor_max_fill_volume_ml: 95.0
reactor_diameter_mm: 50.0
max_temp_to_reduce_heating: 80.0
max_temp_to_disable_heating: 85.0
max_temp_to_shutdown: 90.0

But don’t see anything anywhere. Does it need a reboot?

CamDavidsonPilon · August 11, 2025, 12:48pm

You may need to reboot the web server at least:

sudo systemctl restart lighttpd.service

and then the model should appear as a dropdown on the Inventory page.

The values provided are used throughout the software, and plugins can access these values via

from pioreactor.whoami import get_pioreactor_model

model = get_pioreactor_model()
print(model.reactor_capacity_ml)

CamDavidsonPilon · August 11, 2025, 12:49pm

it also needs to be a yaml file (ends in .yaml, so

mv ~/.pioreactor/models/CB01 ~/.pioreactor/models/CB01.yaml

noahsprent · November 10, 2025, 3:29pm

Sorry but have the 64-bit builds been removed from nightly again? I installed from nightly but didn’t check the file name and have ended up with 32-bit

CamDavidsonPilon · November 10, 2025, 3:38pm

yea sorry, we remove the old nightly images, and if we don’t run 64 bit daily, they will get lost. Let me correct that so they run daily.

CamDavidsonPilon · November 10, 2025, 3:42pm

Heads up: this is a nightly for the next version of Pioreactor, which is pretty different. Important bits:

based on trixie (debian 13) instead of bookworm (debian 12)
web app is now part of the pioreactor package.

full changelog:

github.com/Pioreactor/pioreactor

CHANGELOG.md

develop

### Upcoming

  - Added support for Pioreactor v1.5.
  - `pioreactor.hardware`: reworked GPIO, PWM, and I2C configuration to load from layered YAML mods so new HAT+model combinations can be described without code changes. See new ~/.pioreactor/hardware directories.
  - `pioreactor.hardware`: constants are now resolved lazily through accessor functions (e.g., determine_gpiochip(), get_pwm_to_pin_map()); direct module constants remain but are deprecated shims that emit warnings.
  - export images (PNGs and SVGs) of the Overview's and Calibrations' charts.
  - MCP server: added tools for creating experiments and managing worker assignments
  - Show and hide calibration curves in Calibrations page by clicking the dot beside the calibration (similar to the Overview page).
  - Upgrade to Trixie Debian 13! This mostly means: new Python 3.13.
  - Adding `pio workers update-model <unit> -m <name> -v <version>` to leader's CLI.
  - Added time-window and time-format options to the individual Pioreactors pages.
  - New workflow to set your Pioreactor leader-worker model on first load of the UI.
  - New Pioreactor architecture:
     - New environment variable file /etc/pioreactor.env
     - The old `pioreactorui` Python package is now part of the `pioreactor` Python package, under `pioreactor.web`
     - Moved temporary files from /tmp to /run/pioreactor/
     - New `pioreactor-web.service` to handle both `huey.service` and `lighttpd.service`
  - add new APIs and MCP tools via plugins. Example: drop the following in your ~/.pioreactor/plugins folder:
  ```python
# -*- coding: utf-8 -*-

This file has been truncated. show original

noahsprent · November 10, 2025, 3:49pm

Noted thanks! I actually installed nightly 2025-10-24 so I think I’ve been running that for the last couple of weeks just 32-bit

add new APIs and MCP tools via plugins. Example: drop the following in your ~/.pioreactor/plugins folder:

<3

CamDavidsonPilon · November 10, 2025, 6:23pm

The new 64bit nightly is up again, btw Index of /nightly/leader_worker/

noahsprent · November 10, 2025, 6:24pm

Thanks! Was refreshing the page and installed it about 10 minutes after it was added All seems to be working thanks