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

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Here in this article, we will share some of the most common and frequently asked about PHP problem in programming with detailed answers and code samples. There’s nothing quite so frustrating as being faced with PHP errors and being unable to figure out what is preventing your website from functioning as it should. If you have an existing PHP-based website or application that is experiencing performance issues, let’s get thinking about Allowed memory size of 33554432 bytes exhausted (tried to allocate 43148176 bytes) in php [duplicate].

This error message is being presented, any suggestions?

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

Solution :

If your script is expected to allocate that big amount of memory, then you can increase the memory limit by adding this line to your php file

ini_set('memory_limit', '44M');

where 44M is the amount you expect to be consumed.

However, most of time this error message means that the script is doing something wrong and increasing the memory limit will just result in the same error message with different numbers.

Therefore, instead of increasing the memory limit you must rewrite the code so it won’t allocate that much memory. For example, processing large amounts of data in smaller chunks, unsetting variables that hold large values but not needed anymore, etc.

Here are two simple methods to increase the limit on shared hosting:

  1. If you have access to your PHP.ini file, change the line in PHP.ini
    If your line shows 32M try 64M:
    memory_limit = 64M ; Maximum amount of memory a script may consume (64MB)

  2. If you don’t have access to PHP.ini try adding this to an .htaccess file:
    php_value memory_limit 64M

Your script is using too much memory. This can often happen in PHP if you have a loop that has run out of control and you are creating objects or adding to arrays on each pass of the loop.

Check for infinite loops.

If that isn’t the problem, try and help out PHP by destroying objects that you are finished with by setting them to null. eg. $OldVar = null;

Check the code where the error actually happens as well. Would you expect that line to be allocating a massive amount of memory? If not, try and figure out what has gone wrong…

Doing :

ini_set('memory_limit', '-1');

is never good. If you want to read a very large file, it is a best practise to copy it bit by bit. Try the following code for best practise.

$path = 'path_to_file_.txt';

$file = fopen($path, 'r');
$len = 1024; // 1MB is reasonable for me. You can choose anything though, but do not make it too big
$output = fread( $file, $len );

while (!feof($file)) {
    $output .= fread( $file, $len );


echo 'Output is: ' . $output;

I have faced same problem in php7.2 with laravel 5.6. I just increase the amount of variable memory_limit = 128M in php.ini as my applications demand. It might be 256M/512M/1048M…..Now it works fine.

It is unfortunately easy to program in PHP in a way that consumes memory faster than you realise. Copying strings, arrays and objects instead of using references will do it, though PHP 5 is supposed to do this more automatically than in PHP 4. But dealing with your data set in entirety over several steps is also wasteful compared to processing the smallest logical unit at a time. The classic example is working with large resultsets from a database: most programmers fetch the entire resultset into an array and then loop over it one or more times with foreach(). It is much more memory efficient to use a while() loop to fetch and process one row at a time. The same thing applies to processing a file.

If you want to read large files, you should read them bit by bit instead of reading them at once.
It’s simple math: If you read a 1 MB large file at once, than at least 1 MB of memory is needed at the same time to hold the data.

So you should read them bit by bit using fopen & fread.

I was also having the same problem, looked for phpinfo.ini, php.ini or .htaccess files to no avail. Finally I have looked at some php files, opened them and checked the codes inside for memory. Finally this solution was what I come out with and it worked for me. I was using wordpress, so this solution might only work for wordpress memory size limit problem.
My solution, open default-constants.php file in /public_html/wp-includes folder. Open that file with code editor, and find memory settings under wp_initial_constants scope, or just Ctrl+F it to find the word “memory”. There you will come over WP_MEMORY_LIMIT and WP_MAX_MEMORY_LIMIT. Just increase it, it was 64 MB in my case, I increased it to 128 MB and then to 200 MB.

// Define memory limits.
if ( ! defined( 'WP_MEMORY_LIMIT' ) ) {
    if ( false === wp_is_ini_value_changeable( 'memory_limit' ) ) {
        define( 'WP_MEMORY_LIMIT', $current_limit );
    } elseif ( is_multisite() ) {
        define( 'WP_MEMORY_LIMIT', '200M' );
    } else {
        define( 'WP_MEMORY_LIMIT', '128M' );

if ( ! defined( 'WP_MAX_MEMORY_LIMIT' ) ) {
    if ( false === wp_is_ini_value_changeable( 'memory_limit' ) ) {
        define( 'WP_MAX_MEMORY_LIMIT', $current_limit );
    } elseif ( -1 === $current_limit_int || $current_limit_int > 268435456 /* = 256M */ ) {
        define( 'WP_MAX_MEMORY_LIMIT', $current_limit );
    } else {
        define( 'WP_MAX_MEMORY_LIMIT', '256M' );

Btw, please don’t do the following code, because that’s bad practice:

ini_set('memory_limit', '-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

You can increase the memory allowed to php script by executing the following line above all the codes in the script:

ini_set('memory_limit','-1'); // enabled the full memory available.

And also de allocate the unwanted variables in the script.

ini_set('memory_limit', '-1');

If you are trying to read a file, that will take up memory in PHP. For instance, if you are trying to open up and read an MP3 file ( like, say, $data = file(“” ) it is going to pull it all into memory.

As Nelson suggests, you can work to increase your maximum memory limit if you actually need to be using this much memory.

We had a similar situation and we tried out given at the top of the answers
ini_set(‘memory_limit’, ‘-1’);
and everything worked fine, compressed images files greater than 1MB to KBs.


ini_set('memory_limit', '-1');

in your index.php at the top after opening of php tag

I was receiving the same error message after switching to a new theme in WordPress. PHP was running version 5.3 so I switched to 7.2. That fixed the issue.

If you are using a shared hosting, you will not be able to enforce the increment in the php size limit.

Just go to your cpanel and upgrade your php version to 7.1 and above then you are good to go.

I want to share my experience on this issue!

Suppose you have a class A and class B.

class A {
    protected $userB;

    public function __construct() {
        $this->userB = new B();

class B {
    protected $userA;

    public function __construct() {
        $this->userA = new A();

this will initiate a chain formation of objects which may be create this kind of issue!

I ran the following command composer update, and now are working. If its not solve your problem increase your memory limit in memory_limit in the php.ini file.

wordpress users add line:

@ini_set('memory_limit', '-1');

in wp-settings.php which you can find in the wordpress installed root folder

I hadn’t renewed my hosting and the database was read-only. Joomla needed to write the session and couldn’t do it.

I had the same issue which running php in command line. Recently, I had changes the php.ini file and did a mistake while changing the php.ini

This is for php7.0

path to php.ini where I made mistake: /etc/php/7.0/cli/php.ini

I had set memory_limit = 256 (which means 256 bytes)
instead of memory_limit = 256M (which means 256 Mega bytes).

; Maximum amount of memory a script may consume (128MB)
memory_limit = 128M

Once I corrected it, my process started running fine.

COMPOSER_MEMORY_LIMIT=-1 composer require mageplaza/module-core

wordpress users add line:

@ini_set('memory_limit', '-1');


set memory_limit to -1 in cpanel

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If you are using Laravel, then use these ways:

public function getClientsListApi(Request $request){
      print_r($request->all()); //for all request
      print_r($request->name); //for all name 

instead of

public function getClientsListApi(Request $request){
      print_r($request); // it show error as above mention

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