What is the PHP memory limit for? - PHP memory limit determines how much memory a PHP script can use during its operation. When you run the script, it uses some of your hosting's RAM. This limit is important because it prevents scripts from consuming too much memory, which could slow down performance or cause the site to crash. If a PHP script exceeds this limit, an error will usually occur and the script will stop working.
Note: It is not a good idea to give too much memory to a script if the script does not perform well. For example, if you have 2 GB of RAM in the package, and you set memory_limit to 512 MB, you have actually allowed the bad scripts (if you have them) to take up all the RAM if they run 4 such scripts at the same time. If possible, the goal is to optimize scripts to consume as little as possible, not to allow scripts to have as much memory as possible.
Step 1: Log in to DirectAdmin (instructions).
Step 2: Click on Account Manager in the menu.
Step 3: Click on PHP Settings:

Step 4: In the section called Add New Override in the drop-down menu in the Settings row, select memory_limit:

Step 5: In the Value line, set the value you need:

Step 6: Once you're done, the server will automatically remember your change.