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Table of Contents
How to set max cpu frequency and cores
- Ubuntu
- Android
How to set max cpu frequency
Here are the available cpu frequency sets and you can set one of them as max. cpu frequency using boot.ini
The available list of cpu frequency set
We recommend the following cpu frequency sets under normal conditions.
| frequency | notation on boot.ini |
| 1.656 GHz | “1656” |
| 1.536 GHz | “1536” |
| 1.296 GHz | “1296” |
| 1 GHz | “1000” |
| 500 MHz | “500” |
| 250 MHz | “250” |
| 100 MHz | “100” |
There are some advanced frequency sets you can try below.
The following sets are unstable with 2 or more cpu-cores so, you should adjust cpu cores as described the next section.
| frequency | notation on boot.ini | note |
| 1.680 GHz | “1680” | booting OK with 4 cores / recommend 3 cores for heavy load test |
| 1.752 GHz | “1752” | booting OK with 4 cores / recommend 2 cores for heavy load test |
| 1.896 GHz | “1896” | booing OK with 1~3 cores / recommend running with a single core |
| 1.920 GHz | “1920” | booint OK with 1 or 2 cores / recommend running with a single core |
| 1.944 GHz | “1944” | booting OK with a single core but unstable |
| 2.016 GHz | “2016” | extremely unstable |
setting boot.ini
Please modify max_freq based on the aforementioned frequency table and be sure the unit is MHz.
### boot.ini
# max cpu frequency in dvfs table / in MHz unit
# setenv max_freq "2016" # 2.016GHz
# setenv max_freq "1944" # 1.944GHz
# setenv max_freq "1944" # 1.944GHz
# setenv max_freq "1920" # 1.920GHz
# setenv max_freq "1896" # 1.896GHz
# setenv max_freq "1752" # 1.752GHz
# setenv max_freq "1680" # 1.680GHz
# setenv max_freq "1656" # 1.656GHz
setenv max_freq "1536" # 1.536GHz
# Boot Arguments
# add max_freq in bootargs
setenv bootargs "root=UUID=e139ce78-9841-40fe-8823-96a304a09859 rootwait ro ${condev} no_console_suspend max_freq=${max_freq} hdmimode=${m} ${comde} m_bpp=${m_bpp} vout=${vout} fsck.repair=yes net.ifnames=0 elevator=noop disablehpd=${hpd}"
After setting it, then be sure you do reboot.
You can check the frequency list as following. (example : setenv max_freq “1656”)
root@odroid64:~# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies 100000 250000 500000 1000000 1296000 1536000 1656000
How to set the number of cpu cores
Also, you can set cpu-cores you want to activate using boot.ini
The available range is “1” to “4”
setting boot.ini
### boot.ini
# max cpu-cores
# setenv maxcpus "1"
# setenv maxcpus "2"
# setenv maxcpus "3"
setenv maxcpus "4"
# Boot Arguments
# add maxcpus in bootargs
setenv bootargs "root=UUID=e139ce78-9841-40fe-8823-96a304a09859 rootwait ro ${condev} no_console_suspend max_freq=${max_freq} maxcpus=${maxcpus} hdmimode=${m} m_bpp=${m_bpp} vout=${vout} fsck.repair=yes net.ifnames=0 elevator=noop disablehpd=${hpd}"
