Craft plugin controller for batch update users break with empty page

Question

I made a plugin to update my 3000 users. It is kind of a toolbox to manage and update some users fields.

I am calling the controller directly through its url action.
It is working basically but it stops after 20 seconds when updating too many users, and display a white page in browser, no results.

I can see in my plugin log it updated some few lines before stopping.
I checked php and craft logs and cannot see any error information.

public function actionUsersFix() {

    // Delete all the entry caches
    craft()->templateCache->deleteCachesByElementType('User');

    // Now find the entry IDs
    $criteria = craft()->elements->getCriteria('User', array('group' => 'migMembers', 'limit' => null, 'status' => null, 'localeEnabled' => null));
    $criteria->group = 'migMembers';
    $criteria->limit = null;
    $criteria->status = null;
    $criteria->localeEnabled = null;
    $criteria->accent = '2';

    $userIds = $criteria->ids();
    //$totalEntries = count($userIds);

    //
    foreach ($userIds as $userId)
    {
        $user = craft()->users->getUserById($userId);

        $oldAccent = $user->accent;
        $newAccent = '3';

        $user->getContent()->accent = $newAccent;
        $success = craft()->users->saveUser($user);
        MigPlugin::log('User '.$user->email.' - accent = '. $oldAccent .' - modified = '.$newAccent, LogLevel::Warning);
    }

}

Answer 1

It was a php.ini config problem, I put some parameters values up and the update succeeded in less than 2 minutes and completed my users batch update.

So you just need to update the values below and reload your web server (ie: Apache).

max_execution_time 120 (instead of initial value 30)  
memory_limit 512M (instead of initial value 128M)