Well I'm an idiot - the fulltext index on page_text was missing from a default installation. It didn't break searches but probably slowed them down tremendously. Also set engine to MyISAM on page_text to avoid cryptic error messages from MySQL.
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>blank_page</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
</head>
<body class="mceContentBody">
</body>
</html>