树莓派3b+ usb设备启动 kworker占用cpu高的问题

把sd卡上的系统通过Win32DiskImager做一个img镜像文件到笔记本电脑上，

然后再这个img镜像文件写入到新的usb移动硬盘上。

然后开机启动，成功。

无意间发现top中 kworker1/1 或者1/3的CPU占用率很高，一直在8%-12%之间。我重启了几次设备都一样，没办法，百度上查了好久也没查到多少资料。

然后Google上发现了这个官网的github上的东西，说的就是这个问题，地址：/raspberrypi/linux/issues/2567

解决办法就是：

Thanks a lot. it works.

First the overlay - copying your file to /boot/overlays

and adding line "dtoverlay=sdtweak,poll_once" to /boot/config.txt solved the kworker issue with polling the card.

So far so good :-)

那么这个your file就是在这里/file/d/1JOwJpvWNYbQI4AwwzlQPCJMNehuCFQoy/view?usp=sharing

通过这两步，我发现我重启之后，top中cpu都正常了。

config.txt

# For more options and information see

# http://rpf.io/configtxt

# Some settings may impact device functionality. See link above for details

# uncomment if you get no picture on HDMI for a default "safe" mode

#hdmi_safe=1

# uncomment this if your display has a black border of unused pixels visible

# and your display can output without overscan

#disable_overscan=1

# uncomment the following to adjust overscan. Use positive numbers if console

# goes off screen, and negative if there is too much border

#overscan_left=16

#overscan_right=16

#overscan_top=16

#overscan_bottom=16

# uncomment to force a console size. By default it will be display's size minus

# overscan.

#framebuffer_width=1280

#framebuffer_height=720

# uncomment if hdmi display is not detected and composite is being output

hdmi_force_hotplug=1

# uncomment to force a specific HDMI mode (this will force VGA)

#hdmi_group=1

#hdmi_mode=1

# uncomment to force a HDMI mode rather than DVI. This can make audio work in

# DMT (computer monitor) modes

#hdmi_drive=2

# uncomment to increase signal to HDMI, if you have interference, blanking, or

# no display

#config_hdmi_boost=4

# uncomment for composite PAL

#sdtv_mode=2

#uncomment to overclock the arm. 700 MHz is the default.

#arm_freq=800

# Uncomment some or all of these to enable the optional hardware interfaces

#dtparam=i2c_arm=on

#dtparam=i2s=on

#dtparam=spi=on

# Uncomment this to enable the lirc-rpi module

#dtoverlay=lirc-rpi

# Additional overlays and parameters are documented /boot/overlays/README

# Enable audio (loads snd_bcm2835)

dtparam=audio=on

dtoverlay=sdtweak,poll_once