when using a DFS cluster, sometimes files named expiryXXXtmp.php appear with 0 bytes, or the expiry.php file has 0 bytes.

the error is random this behaviour only shows with very high traffic that stresses the servers enough to cause the error.

Steps to reproduce

there is no known way to reproduce the error in a regular environment. the only test is to use xdebug, stop ececution and artificially corrupt the file being handled by the eZDFSFileHandlerMySQLBackend::_fetch() funtion.