This afternoon, the service of this website was unavailable. Like the day before yesterday, the disk's IO wait time and busy ratio remained high, and the CPU usage rate could not be obtained. The panel and SSH could not be accessed. The problem was solved by itself after waiting for two hours the day before yesterday afternoon, but the problem occurred at three o'clock this afternoon and lasted for nearly five hours.
In the evening, I submitted a ticket to Tencent Cloud, and Tencent Cloud indicated that it was a "memory overflow" issue. After creating a snapshot of the disk, I restarted the host instance. Except for the panel, all other services returned to normal and no data was lost.
Today, a cold wind brings hopeful air. As Luo Xiang said, we should be cautious with controllable things and brave and confident with uncontrollable things. 2022 has passed.
WordPress seems to have a little problem. The front end is completely normal, but some scripts in the back end are malfunctioning, and the console is all red. Maybe, as Teacher Du said, I am still too good at tinkering. This year, I may have to tinker with the website again.