This afternoon, the service of this website is not available. Like the day before yesterday, the disk IO wait time and busy ratio have been high, CPU usage cannot be obtained, and both the panel and SSH cannot be accessed. The problem was solved by itself after waiting for two hours the day before yesterday afternoon, but the problem appeared at three o'clock this afternoon and lasted for nearly five hours, still abnormal.
In the evening, I submitted a ticket to Tencent Cloud, and Tencent Cloud indicated "memory overflow." After creating a hard disk snapshot, I restarted the host instance, and all services except the panel returned to normal, with no data loss.
Today, the cold wind brings air full of hope. As Luo Xiang said, we should be careful with controllable things and brave and confident with uncontrollable things. 2022 has passed.
It seems that WordPress has encountered some problems. The front end is completely normal, but some scripts in the back end have failed, 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.