I am overclocking my raspberry pi. I have selected the turbo option from the raspi-config. I have found out however that the Pi was not running consistently at 1GHz. I have tried setting the governor (in root using echo ...) to "performance" however it reverts to the default "on demand" after reboot. I need the pi to run consistently at 1 GHz so I decided to select the force_turbo=1 at config.txt. However, it does not run consistently at the set arm frequency but runs at the default 700MHz even at 45% cpu load while running my code. I have check the temperature, cpu load, and arm_freq using vcgencmd (get_config, measure_temp, measure_clock) command.
Isn't the force turbo option suppose to disable dynamically changing clock frequencies and set the arm frequency set at config.txt consistently even at low load?
Here's my config.txt:
gpu_mem=64 start_x=1 dtparam=spi=on dtparam=i2c1=on dtparam=i2c1_baudrate=400000 dtparam=i2c_arm=on dtparam=i2c_arm_baudrate=400000 force_turbo=1 arm_freq=1000 core_freq=500 sdram_freq=600 over_voltage=6
Here's my rc.local:
#!/bin/sh -e # # rc.local # # This script is executed at the end of each multiuser runlevel. # Make sure that the script will "exit 0" on success or any other # value on error. # # In order to enable or disable this script just change the execution # bits. # # By default this script does nothing. sudo echo performance > sys/devices/system/cpu/cpu0/cpufreq/scaling_governor exit 0
I have found the culprit. It was an undervoltage problem due to what supply I used. The problem was solved by using a separate supply. An indicator of an undervoltage problem is the appeareance of a multicolored square at the upper right corner of the desktop as well as the simultaneous flickering/blinking of the red power led of the pi. Undervoltage automatically disables force turbo to protect from sd card corruption.
/etc/rc.local. It is pointless since the script is run root by init, won't work with redirection (
>) under any circumstances, and may cause that to fail if there is no path (the shell has an
echobuilt-in, so that is okay). Also (this has nothing to do with your problem),
start_x=1enables the camera but you probably won't be able to use it unless
gpu_memis >= 128.