在nginx / php-fpm配置上同时运行脚本的限制是什么？

Question

The problem is I have to use curl and sometimes the curl requests take a long time because of the timeouts. I have set the timeouts to 1 second so no request should take more than 1 second but still the server is unable to process other php requests.

My question is how many concurrent scripts(running at the same time) can nginx/php-fpm handle. What I see is that a few requests lasting 1 second make the whole server unresponsive. What are the settings that I can change so more requests can be processed at the same time?

Answer 1

Php-curl did not respond in a timely manner because of DNS.

The problem was that I had to access files from a CDN but the IP behind the domain changed frequently and unfortunately curl keeps a DNS cache.

So from time to time it would try to access files from IPs that were not valid anymore, but they were still in the DNS cache of php-curl.

I had to drop php-curl completely and use a plain file_get_contents(...) request. This completely solved the problem.