If your site experiences slow or unusable performance when viewing the "Files" section in the CMS, it could be due to your site containing an excessive number of files. Symptoms of this issue could include the files section failing to load, loading for a long period of time, or a warning notification when attempting to view that section.

The cause of this issue is the file "tree" view in the files section, which does not support the pagination of list view, which allows it to limit visibility to a single page of files.

The resolution of this issue is to customise the AssetAdmin class to remove the tree view. The list view, which does not suffer from performance degradation over multiple files, will still be able to be used to navigate files as per normal.

Place the below code into a PHP class under mysite/ folder, and then apply the appropriate YML configuration to replace the existing class via dependency injection.



use SilverStripe\AssetAdmin\Controller\AssetAdmin;

class SimpleAssetAdmin extends AssetAdmin
    public function getEditForm($id = null, $fields = null) 
        $form = parent::getEditForm($id, $fields);
        return $form;

    public function SiteTreeAsUL() {
        return null;


Name: myassetadmin
    class: SimpleAssetAdmin

(Optional) In some instances, you may notice that you have two "Files" menu items. To remove the now unused "Files" menu item, add the following to your _config.php.



After making these changes, flush the site with ?flush=1 in your querystring, and the assets area will load much more quickly.

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