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.
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
Database may be too large?
"Due to the limited execution time and memory available to PHP, backing up very large databases may not be possible. If your database is very large you might need to backup directly from your SQL server via the command line, or have your server admin do it for you if you do not have root privileges."
http://www.codeigniter.com/user_guide/database/utilities.html
Edit: As @E_p states, you're running out of memory, but my answer is probably the most likely cause of the error...
Edit 2:
As noted in another answer, I would strongly caution you to not use set your memory usage to unlimited ini_set('memory_limit', '-1');, especially if you're on a shared server.