php怎么监控varnish缓存服务器状态？

$outfile=shell_exec("/usr/bin/varnishstat -x");
$xml=simplexml_load_string($outfile);
echo $xml->getName() . "";
foreach($xml->children() as $child)
{
//$tmpName="";
foreach($child->children() as $subChild)
{
if ($subChild->getName() =="name" )
 {
$tmpName=$subChild;
}
elseif ($subChild->getName() =="value" )
{
if ($tmpName!="")
{
 $arys["$tmpName"]=$subChild;
 $tmpName="";
}
}
else
 {
continue;
}
}
}
function byteReduce($bytes)
{
if ($bytes>1099511627776)
{
return round($bytes/1099511627776)."TB";
}
else if ($bytes > 1073741824)
{
return round($bytes/1073741824)."GB";
}
else if ($bytes>1048576)
{
return round($bytes/1048576)."MB";
}
else if ($bytes>1024)
{
return round($bytes/1024)."KB";
}
else
{
return $bytes."B";
}
}
echo "client_conn: ".$arys["client_conn"] . "";
echo "client_req: ".$arys["client_req"] . "";
echo "cache_hit: ".$arys["cache_hit"] . "";
echo "cache_miss: ".$arys["cache_miss"] . "";
echo "Cache hit rate: ".round(($arys["cache_hit"]/$arys["client_req"])*100)." % ";
echo "LRU nuked objects: ".$arys[n_lru_nuked]."";
echo " ".byteReduce($arys["s_bodybytes"]+$arys["s_hdrbytes"])." Acc Content (".byteReduce($arys["s_hdrbytes"])." header ".byteReduce($arys["s_bodybytes"])." Body)";
?>

效果，如下图：

备注，为了查看实时情况，可以在在监控页加个html定时刷新，可以随时查看varnish缓存服务器状态。