Space Admin loads slowly for large spaces

public class EditSpaceEntryAction extends AbstractEditSpaceAction
{
    public List getAvailablePages()
    {
        if ((availablePages == null) && (getSpace() != null))
        {
            availablePages = new ArrayList(pageManager.getPages(getSpace(), true));
            Page blankPageAtTop = new Page();
            blankPageAtTop.setTitle("");
            availablePages.add(0, blankPageAtTop); // Give user the option not to select any home page
        }
        Collections.sort(availablePages);

        return availablePages;
    }

    public void setSpaceManager()
    {
    }
}