Periodic load on the server, how to track and block if necessary?

Question

linux

Right now, the server periodically takes off the CPU, it slows down

As you can see, the httpd load:

How to understand where exactly it comes from?

Answer 1

Что то уж пики слишком идут через подозрительно равные интервалы. Как по cron'у обращения к сайту, либо парсер чей-то.
Можно начать проверять логи вебсервера, с группировкой по IP адресу кол-во запросов в интервале времени, например 10 минут.

Answer 2

strace, tcpdump+wireshark, feed elk with logs for starters.

Answer 3

iotop -oka and watch while booting

Answer 4

Take Python, write a parser and catch ip addresses that carry either a load or an interval of appearance on the network. Of course, I'm not talking about the server master, but once my more experienced friend solved it in such ways. Perhaps those who understand will throw slippers, but I gave a tip about.