XML data not reading fully

Hai folks,

i am using below code to parse a large xml file.
problem is, it's not reading the entire xml data,rather a small portion is only read.
what could be the problem?

$file  = "$url"; 
function contents($parser, $data){
    echo $data;
}
function startTag($parser, $data){
    echo "<b>";
}
function endTag($parser, $data){
    echo "</b><br />";
}

$xml_parser = xml_parser_create();
xml_set_element_handler($xml_parser, "startTag", "endTag");
xml_set_character_data_handler($xml_parser, "contents");
$fp = fopen($file, "r");
$data = fread($fp, 80000); // Note i increased the size of this up to 2mb and result is same.
if(!(xml_parse($xml_parser, $data, feof($fp)))){
    die("Error on line " . xml_get_current_line_number($xml_parser));
}
xml_parser_free($xml_parser);
fclose($fp);

PHP: