How to fix PHP Fatal error: Out of memory error?

Question

PHP

Hello
, my server is down, error 502 for 25 minutes, I see the following in the logs:

2017/08/19 19:36:30 [error] 7652#0: *978 upstream sent unexpected FastCGI record: 3 while reading response header from upstream, client: 207.46.13.158, server: vamdodoma.ru, request: "GET /catalog/2-mestnye-divany/S39861885.html/ HTTP/1.1", upstream: "fastcgi://unix:/var/php-nginx/14617404421463.sock/socket:", host: "vamdodoma.ru"

2017/08/19 19:36:31 [error] 7651#0: *622 FastCGI sent in stderr: "PHP Fatal error: Out of memory (allocated 262144) (tried to allocate 8589938688 bytes) in Unknown on line 0" while reading response header from upstream, client: 46.237.19.175, server: vamdodoma.ru, request: "GET /api/app.getCities HTTP/1.1", upstream: "fastcgi://unix:/var/php-nginx/14617404421463.sock/socket:", host: "vamdodoma.ru"

2017/08/19 19:36:31 [error] 7651#0: *622 upstream sent unexpected FastCGI record: 3 while reading response header from upstream, client: 46.237.19.175, server: vamdodoma.ru, request: "GET /api/app.getCities HTTP/1.1", upstream: "fastcgi://unix:/var/php-nginx/14617404421463.sock/socket:", host: "vamdodoma.ru"

server PHP, NGINX, MySQL
в php.ini memory_limit = 48000M
Why is there not enough memory, how can I overcome this problem so that the site does not lie for 25 minutes?
Thanks in advance for your help!

Answer 1

Well, it’s also written there that you are trying to allocate eight gigabytes of memory, if you just increase the memory in a stupid way, in the phpfpm logs there is usually a stack of function calls to understand what is wrong

Answer 2

Optimize the code, for example, change gd to imagemagick

Answer 3

When processing - give up cycles and use generators.
Most likely - a large amount of data gets into the array after sampling from the database and ... prev!