When an error like "Fatal error: Allowed memory size of 8388608 bytes exhausted (tried to allocate 775920 bytes)" occurs, first of all First check whether there is an infinite loop in your php program.
Solutions (three types):
1. Modify php.ini (recommended)
Memory_limit = 12M
2. Add the following statements in the program
ini_set('memory_limit', '12M');
3. Create
in the root directory.htaccess file, add the following content
php_value memory_limit 12M
If it still doesn’t work, make it bigger.
The last thing to note is to restart the server.