Allowed memory size of 33554432 bytes exhausted (tried to allocate 43148176 bytes) in php

Question

This error message is being presented, any suggestions?

Allowed memory size of 33554432 bytes exhausted (tried to allocate 43148176 bytes) in php

Answer 1

I notice many answers just try to increase the amount of memory given to a script which has its place but more often than not it means that something is being too liberal with memory due to an unforseen amount of volume or size. Obviously if your not the author of a script your at the mercy of the author unless your feeling ambitious :) The PHP docs even say memory issues are due to "poorly written scripts"

It should be mentioned that ini_set('memory_limit', '-1'); (no limit) can cause server instability as 0 bytes free = bad things. Instead, find a reasonable balance by what your script is trying to do and the amount of available memory on a machine.

A better approach: If you are the author of the script (or ambitious) you can debug such memory issues with xdebug. The latest version (2.6.0 - released 2018-01-29) brought back memory profiling that shows you what function calls are consuming large amounts of memory. It exposes issues in the script that are otherwise hard to find. Usually, the inefficiencies are in a loop that isn't expecting the volume it's receiving, but each case will be left as an exercise to the reader :)

The xdebug documentation is helpful, but it boils down to 3 steps:

1. Install It - Available through apt-get and yum etc
2. Configure it - xdebug.ini: xdebug.profiler_enable = 1, xdebug.profiler_output_dir = /where/ever/
3. View the profiles in a tool like QCacheGrind, KCacheGrind