Debugging 504 Gateway Timeout and its actual cause and solution

[itpp2012]

Keyur Wrote:
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> If its poorly written code then I need to inform the developer that
> 504 is happening due to issue in php code and not due to nginx or
> php-fpm and if its due to Nginx or Php-fpm then need to fix that.

How many php master/slave processes are running generally and how many when
you get 5xx errors?
It is best to define and use a pool (upstream) for php.

Posted at Nginx Forum: https://forum.nginx.org/read.php?2,263842,263845#msg-263845