Fatal Error: Allowed Memory Size of 134217728 Bytes Exhausted (CodeIgniter + XML-RPC)


I have a bunch of client point of sale (POS) systems that periodically send new sales data to one centralized database, which stores the data into one big database for report generation.

The client POS is based on PHPPOS, and I have implemented a module that uses the standard XML-RPC library to send sales data to the service. The server system is built on CodeIgniter, and uses the XML-RPC and XML-RPCS libraries for the webservice component. Whenever I send a lot of sales data (as little as 50 rows from the sales table, and individual rows from sales_items pertaining to each item within the sale) I get the following error:

Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 54 bytes)

128M is the default value in php.ini, but I assume that is a huge number to break. In fact, I have even tried setting this value to 1024M, and all it does is take a longer time to error out.

As for steps I've taken, I've tried disabling all processing on the server-side, and have rigged it to return a canned response regardless of the input. However, I believe the problem lies in the actual sending of the data. I've even tried disabling the maximum script execution time for PHP, and it still errors out.

11/3/2017 7:40:30 PM

ini_set('memory_limit', '-1'); overrides the default PHP memory limit.


The correct way is to edit your php.ini file. Edit memory_limit to your desire value.

As from your question, 128M (which is the default limit) has been exceeded, so there is something seriously wrong with your code as it should not take that much.

If you know why it takes that much and you want to allow it set memory_limit = 512M or higher and you should be good.


The memory allocation for PHP can be adjusted permanently, or temporarily.


You can permanently change the PHP memory allocation two ways.

If you have access to your php.ini file, you can edit the value for memory_limit to your desire value.

If you do not have access to your php.ini file (and your webhost allows it), you can override the memory allocation through your .htaccess file. Add php_value memory_limit 128M (or whatever your desired allocation is).


You can adjust the memory allocation on the fly from within a PHP file. You simply have the code ini_set('memory_limit', '128M'); (or whatever your desired allocation is). You can remove the memory limit (although machine or instance limits may still apply) by setting the value to "-1".


It's very easy to get memory leaks in a PHP script - especially if you use abstraction, such as an ORM. Try using Xdebug to profile your script and find out where all that memory went.


When adding 22.5 million records into an array with array_push I kept getting "memory exhausted" fatal errors at around 20M records using 4G as the memory limit in file php.ini. To fix this, I added the statement

$old = ini_set('memory_limit', '8192M');

at the top of the file. Now everything is working fine. I do not know if PHP has a memory leak. That is not my job, nor do I care. I just have to get my job done, and this worked.

The program is very simple:

$fh = fopen($myfile);
while (!feof($fh)) {
    array_push($file, stripslashes(fgets($fh)));

The fatal error points to line 3 until I boosted the memory limit, which eliminated the error.