Help me analyze it

You can help me analyze a server that is currently running & nbsp; for data statistics. the previous run was still stable and there was no major problem. & nbsp; however, I suddenly found out from yesterday, the apache process is full, and the mysql process is full. the whole server becomes very stuck. & nbsp; my first thought may be the problem of Mysql. could you help me analyze it?
At present, there is a server for data statistics. the previous run was still stable and there was no major problem. However, from yesterday, we suddenly found that the apache process was full and the mysql process was full, the whole server is very slow. I felt it was probably a problem with Mysql. I had to wait 20 or 30 seconds to query an SQL statement, and the writing speed was very slow. I don't know why, it is initially believed that the apache process is congested due to low execution efficiency of Mysql. I didn't understand it all night. I found that the response was normal this morning. it may be because the data volume was small in the morning and now it is suspended again, I want to know what will cause the server to become very stuck, resulting in Mysql, and the execution efficiency will be reduced:
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Optimizing your programs and SQL commands may improve your situation.

You also need to consider other factors. after all, the server is not designed for your website.
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Check the log to see if valid information can be found.