How to change the maximum allowed page size in MediaWiki
In MediaWiki there's an option with which you can change how big (in terms of file size) can an article be. If a user puts content in the page that exceeds the allowed size, they will not be allowed to save the change. They have to reduce the content so that it fits into the specified size. The size is set in kilobytes and by default it's set to 2048, which equals around 2 megabytes. This is more than sufficient even for very big pages.
If you want to reduce the allowed article size (or increase it anyway), you can do that by modifying the LocalSettings.php file of your MediaWiki. On a new line at the end of the file insert a line that looks like this:
$wgMaxArticleSize = 100;
Set the number to whatever size you want. As we mentioned it's in kilobytes. In our example the maximum article size is set to 100 kilobytes.
To view what the size of the current (and other revisions) of the page is, open the page on the frontend and view its history (with the View history button in the top right corner). In brackets for each revision you'll see its size; it's also indicated with how much it's changed compared to the previous revision.
The LocalSettings.php file that you have to edit is located in the root MediaWiki folder on your MediaWiki hosting account. If the application is installed in the public_html directory on your account, then the path to the file will be public_html/LocalSettings.php. HostKnox customers can use the File manager of the Pixie control panel to view and edit files on the account. Another option is to download it on your local computer, edit it with a text editor (e.g. Notepad ++) and upload it back. Files can also be edited on the account via SSH.