Hello
I downloaded a fresh copy of BBB-eMMC-flasher-ubuntu-18.04.1-console-armhf-2018-12-10-2gb.img.xz
I created a bootable Mircro-SD card and flashed a spare BBB
at first boot i ran
sudo apt update; sudo apt upgrade -y
sudo apt dist-upgrade -y
sudo apt remove nginx nginx-common avahi-daemon
rebooted BBB
service --status-all
[ - ] acpid
[ - ] alsa-utils
[ - ] avahi-daemon
[ - ] bluetooth
[ + ] connman
[ - ] console-setup.sh
[ + ] cpufrequtils
[ + ] cron
[ - ] cryptdisks
[ - ] cryptdisks-early
[ + ] dbus
[ + ] dnsmasq
[ + ] fake-hwclock
[ + ] grub-common
[ + ] haveged
[ - ] hostapd
[ - ] hwclock.sh
[ - ] keyboard-setup.sh
[ + ] kmod
[ + ] loadcpufreq
[ + ] networking
[ - ] nginx
[ - ] plymouth
[ - ] plymouth-log
[ - ] pppd-dns
[ + ] procps
[ - ] rsync
[ + ] rsyslog
[ + ] ssh
[ + ] udev
[ - ] udhcpd
edited /etc/init.d/cpufrequtils
ENABLE=“true”
GOVERNOR=“conservative”
MAX_SPEED=“0”
MIN_SPEED=“0”
saved it and exited nano
rebooted BBB
sudo cpufreq-info
analyzing CPU 0:
driver: cpufreq-dt
CPUs which run at the same hardware frequency: 0
CPUs which need to have their frequency coordinated by software: 0
maximum transition latency: 300 us.
hardware limits: 300 MHz - 1000 MHz
available frequency steps: 300 MHz, 600 MHz, 720 MHz, 800 MHz, 1000 MHz
available cpufreq governors: conservative, ondemand, userspace, powersave, performance
current policy: frequency should be within 300 MHz and 1000 MHz.
The governor “ondemand” may decide which speed to use
within this range.
current CPU frequency is 1000 MHz (asserted by call to hardware).
cpufreq stats: 300 MHz:88.72%, 600 MHz:1.43%, 720 MHz:0.11%, 800 MHz:0.15%, 1000 MHz:9.60% (279)
the above output is showing ‘ondemand’ governor is in use and not ‘conservative’
if i go back to the /etc/init.d/cpufrequtils
ENABLE=“true”
GOVERNOR=“conservative”
MAX_SPEED=“1000”
MIN_SPEED=“300”
reboot BBB
then run cpufreq-info
analyzing CPU 0:
driver: cpufreq-dt
CPUs which run at the same hardware frequency: 0
CPUs which need to have their frequency coordinated by software: 0
maximum transition latency: 300 us.
hardware limits: 300 MHz - 1000 MHz
available frequency steps: 300 MHz, 600 MHz, 720 MHz, 800 MHz, 1000 MHz
available cpufreq governors: conservative, ondemand, userspace, powersave, performance
current policy: frequency should be within 300 MHz and 300 MHz.
The governor “conservative” may decide which speed to use
within this range.
current CPU frequency is 300 MHz (asserted by call to hardware).
cpufreq stats: 300 MHz:56.08%, 600 MHz:0.00%, 720 MHz:0.00%, 800 MHz:0.00%, 1000 MHz:43.92% (1)
it now shows that it is using the ‘conservative’ governor however when i put a load on it … i open 3 more ssh terminals and run cmatrix on them all and open another ssh terminal and run htop
htop reports cpu at 97.2%
cpufreq-info
analyzing CPU 0:
driver: cpufreq-dt
CPUs which run at the same hardware frequency: 0
CPUs which need to have their frequency coordinated by software: 0
maximum transition latency: 300 us.
hardware limits: 300 MHz - 1000 MHz
available frequency steps: 300 MHz, 600 MHz, 720 MHz, 800 MHz, 1000 MHz
available cpufreq governors: conservative, ondemand, userspace, powersave, performance
current policy: frequency should be within 300 MHz and 300 MHz.
The governor “conservative” may decide which speed to use
within this range.
current CPU frequency is 300 MHz (asserted by call to hardware).
cpufreq stats: 300 MHz:92.52%, 600 MHz:0.00%, 720 MHz:0.00%, 800 MHz:0.00%, 1000 MHz:7.48% (1)
once again edit the /etc/init.d/cpufrequtils
ENABLE=“true”
GOVERNOR=“conservative”
MAX_SPEED=“1000”
MIN_SPEED=“0”
save and exit nano
rebooted BBB
cpufreq-info
analyzing CPU 0:
driver: cpufreq-dt
CPUs which run at the same hardware frequency: 0
CPUs which need to have their frequency coordinated by software: 0
maximum transition latency: 300 us.
hardware limits: 300 MHz - 1000 MHz
available frequency steps: 300 MHz, 600 MHz, 720 MHz, 800 MHz, 1000 MHz
available cpufreq governors: conservative, ondemand, userspace, powersave, performance
current policy: frequency should be within 300 MHz and 1000 MHz.
The governor “ondemand” may decide which speed to use
within this range.
current CPU frequency is 1000 MHz (asserted by call to hardware).
cpufreq stats: 300 MHz:60.50%, 600 MHz:2.38%, 720 MHz:0.14%, 800 MHz:0.17%, 1000 MHz:36.80% (123)
i am still unable to get the desired outcome for an idle CPU at 300 MHz and ramp up dynamically as needed until all events/processes are finished and returning back to 300 MHz
i recreated this as i wrote this post so as to not be misleading i hope this helps.
maybe its me missing something but it seams that the cpufreq-dt driver might not be applying the ‘conservative’ governor properly
if there is any other information you need please let me know and i will do my best, i am at a loss for other options to try.
PS. it would be soooooo nice to regain access to the CPU temp sensor …
then i could use it to control a fan with a heat sink
once again thank you for your time. 