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From: druck <news@druck.org.uk>
Newsgroups: comp.sys.raspberry-pi
Subject: 1-wire behaviour on Bookworm
Date: Thu, 19 Sep 2024 10:36:16 +0100
Organization: A noiseless patient Spider
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After getting another Pi 5, I've moved a Pi 4B running Bookworm in to 
the role taken by a Pi 3B running Bullseye, which is monitoring 6 
ds18b20 sensors, configured as 2 1-wire buses with 3 sensors on each.

With the Pi 3B, I could either read the sensors sequentially taking 
about 0.9s each, or using threads simultaneously in 1.0s. The Pi 4B with 
Bookworm reads the sensors sequentially a shade faster at just over 
0.8s, but when reading simultaneously, returns 2 after 0.8s, another 2 
after 1.6s and the last two at 2.4s.

Anyone have an explanation for this?

It's not a problem as I changed some time ago from performing one 
simultaneous read every 5 minutes to reading sequentially every minute 
and averaging over 15 minutes.

---druck