Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 91 bytes) error while trying to backup database

Question

I got Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 91 bytes) error while trying to backup database on online rest server using Codeigniter dbutil backup() function.

Here is my code:

    $this->load->dbutil();
    $backup =& $this->dbutil->backup(); 
    $this->load->helper('file');
    write_file('./uploads/db/mybackup.gz', $backup);

I can't find out where I am doing wrong.

php.net/manual/en/ini.core.php#ini.memory-limit . You just used all the memory that was allowed by PHP setup. Increase value in php.ini. And next time read error as clearly states problem. — E_p
I can increase memory limit on php.ini from local server. How could I increase php.ini value in online server? — Sazzad-Ul Islam
If u dont have access on production than use ini_set function as I suggest — devpro
You should look into native mysqldump rather than relying on CodeIgniter to basically fill up PHP's memory with a bunch of $output.= 'insert into...'; and then writing the output to the disk. — MonkeyZeus
In CodeIgniter 2.1.4 at least, go to /system/database/drivers/mysql/mysql_utility.php and find the function _backup() to see exactly why your memory is being exhausted. The issue is that the utility is not streaming the data to a file but it is trying to load all of the bytes into memory. — MonkeyZeus

devpro devpro · Accepted Answer · 2016-01-12T16:53:44

You need to increase your script memory by using this:

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

You need to use this line at the top of file.

By increasing memory_limit your script will take unlimited memory usage of server.

If you have access on php.ini file than you can increase limit from php.ini file otherwise you need to add this line.

Side note:

If you think unlimited memory will be effected on other areas than you can set custom value as:

ini_set('memory_limit', '512M');  //increase size as you need

Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 91 bytes) error while trying to backup database

2 Answers