I have running Nginx + Php-fpm. Php has limit of max_childs = 20. So, it is able to accept only 20 connections at single time. So, there are 2 questions:
How to differentiate Nginx timeouts for waiting for "free" php child with time for waiting php child actually "working" time?
Or how to make Php not to enqueue requests, which do not fit to max_children limit? And just quickly reject connection if there are no "free" child?
Because it causes some problem. If Nginx have fastcgi read timeout, for example 60s, and php script executes 20s.
So, if Nginx wait for "free" php child for more than 40s, there is no sense to begin php execution at all, because Nginx still can not wait for its answer due to timeout.