關閉樹莓派的優化筆記

一、關閉HDMI輸出

/opt/vc/bin/tvservice -o

二、關閉模塊

vi /etc/modules

#snd-bcm2835

三、關閉USB電流限制

因樹莓派的USB接口電流大小由USB電流保護芯片進行限制，因此經過旁路USB電流保護芯片（即不讓電流從電流保護芯片流過）就能夠實現更大電流。

具體配置須要修改 /boot/config.txt 這個文件，在最後面添加三行。

max_usb_current=1
current_limit_override=0x5A000020
avoid_warnings=2

 

因爲電源芯片限制，最大電流爲1.2A。從新啓動樹莓派便可生效

四、超頻，強制主頻 (按官方文檔：https://www.raspberrypi.org/documentation/configuration/config-txt/overclocking.md)

修改/boot/config.txt

arm_freq=1400


        Frequency of the ARM CPU in MHz; default value is 1000 for the Pi Zero and Pi Zero W, 700 for Pi 1, 900 for Pi 2, 1200 for the Pi 3, 1400 for the Pi 3B+, 1500 for the Pi 4B

core_freq=500

        Frequency of the GPU processor core in MHz, influences CPU performance because it drives the L2 cache and memory bus; default value is 250 for the Pi 1/Pi 2, and 400 for the Pi 3/Pi Zero/Pi Zero W; the L2 cache benefits only the Pi Zero/Pi Zero W/ Pi 1, there is a small benefit for SDRAM on the Pi 2/Pi 3, and there is no effect on the SDRAM on the Pi 4B

五、使用Dietpi版本時關閉SWAP

臨時狀況：swapoff -a

想要永久關閉SWAP: 須要修改/boot/dietpi.txt和/DietPi/dietpi.txt兩個文件裏面的SWAP設備，而後重啓

 六、樹莓派獲取硬件信息：

https://github.com/raspberrypi/documentation/blob/JamesH65-patch-vcgencmd-vcdbg-docs/raspbian/applications/vcgencmd.md