关闭树莓派的优化笔记

一、关闭HDMI输出

/opt/vc/bin/tvservice -o

二、关闭模块

vi /etc/modules

#snd-bcm2835

三、关闭USB电流限制

因树莓派的USB接口电流大小由USB电流保护芯片进行限制，因此经过旁路USB电流保护芯片（即不让电流从电流保护芯片流过）就能够实现更大电流。

具体配置须要修改 /boot/config.txt 这个文件，在最后面添加三行。

max_usb_current=1
current_limit_override=0x5A000020
avoid_warnings=2

 

因为电源芯片限制，最大电流为1.2A。从新启动树莓派便可生效

四、超频，强制主频 (按官方文档：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版本时关闭SWAP

临时状况：swapoff -a

想要永久关闭SWAP: 须要修改/boot/dietpi.txt和/DietPi/dietpi.txt两个文件里面的SWAP设备，而后重启

 六、树莓派获取硬件信息：

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