What if the server CPU is full?

1, check whether the maximum number of threads of the program is sufficient; 2, the program code is not optimized enough, such as infinite loop, deadlock; 3, whether the parameters of the web configuration file are not optimized; 4, check the web and system logs to see if there is access abnormality; 5 Whether the website has been stolen or not; 6. Is there a search engine crawler crawling the website in a large area at that time; 7. Is it a small network attack; whether the process is abnormal; 8. Check whether the machine is poisoned or trojan; linux server can pass the system. Logs and web logs, and some top, free, uptime, sar, ps commands to query the reasons, windows machines can be analyzed through the resource monitor.