php优化,该怎么处理

php优化

<?php<br />//define server info begin<br />$servername = "192.168.1.182";  <br />$serverusername = "whh";  <br />$serverpassword = "whh"; <br />$database="whh";<br />$usertable="user";<br />$userfield="user_name";<br />$passwordfield="password";<br />//define server info end<br /><br />$fh  = fopen("php://stdin", 'r');<br />$stdout = fopen('php://stdout', 'w');<br />$fs = fopen("auth-log.txt." . getmypid(), 'a');<br /><br />if(!$fh){<br />    die("Cannot open STDIN\n");<br />}<br /><br />do{<br />    $lenBytes = fgets($fh, 3);<br />    $len = unpack('n', $lenBytes);<br />    $len = $len[1];<br />    if($len<1) continue;<br />    $msg = fgets($fh, $len+1);<br />    $toks=explode(':',$msg);<br />    fwrite($fs, $msg . "\n");<br /><br />    $method = array_shift($toks);<br />    fwrite($fs, "$method\n");<br />    $result = false;<br /><br />    switch($method){<br />        case 'auth':<br />            list($username, $server, $password) = $toks;<br />            $password = trim($password);<br />            fwrite($fs, "checking user: $username and password $password\n");<br />            //check password begin<br />						$conn=mysql_connect($servername, $serverusername, $serverpassword); <br />						mysql_query("set names 'utf8'");<br />						if(!$conn){                              <br />						  die("could not connect to the database");<br />						}<br />						$db_select=mysql_select_db($database);//选择数据库        <br />						if(!$db_select)<br />						{<br />						  die("could not to the database");<br />						}<br />						$query="select * from $usertable where $userfield = '$username' and $passwordfield='$password'";//构建查询语句<br />						$result=mysql_query($query);//执行查询<br />						$count=mysql_numrows($result);//取得条数<br />						mysql_close($conn);<br />						if($count > 0){<br />							$result = true;<br />						}else{<br />							$result = false;<br />						}<br />						//check password end<br />            break;<br /><br />        case 'isuser':<br />            list($username, $server) = $toks;<br />            //check password begin<br />						$conn=mysql_connect($servername, $serverusername, $serverpassword); <br />						mysql_query("set names 'utf8'");<br />						if(!$conn){                              <br />						  die("could not connect to the database");<br />						}<br />						$db_select=mysql_select_db($database);//选择数据库        <br />						if(!$db_select)<br />						{<br />						  die("could not to the database");<br />						}<br />						$query="select * from $usertable where $userfield = '$username'";//构建查询语句<br />						$result=mysql_query($query);//执行查询<br />						$count=mysql_numrows($result);//取得条数<br />						mysql_close($conn);<br />						if($count > 0){<br />							$result = true;<br />						}else{<br />							$result = false;<br />						}<br />						//check password end<br />            break;<br /><br />        default:<br />            $result = false;<br />    }<br />        $message =  @pack("nn", 2, $result);<br />        fwrite($stdout, $message);<br />        $dump = @unpack("nn", $message);<br />        $dump = $dump["n"];<br />        fwrite($fs, $dump . "\n");<br />        flush();<br />} while(true);

大家好！
对php我不懂，请大家看下是否可以对该php做些优化呢?
我是写java的，发现可能在这个地方“$conn=mysql_connect($servername, $serverusername, $serverpassword);”可以进行优化，没有必要每次都生成一个$conn。
------解决方案--------------------
没有什么可优化的
在传入的数据中，可能只有 auth，也可能只有 isuser，更可能两者都没有
完全没有必要在可能无需数据库访问的情况下，做数据库连接

程序的优化不是减少代码，而是提升性能
------解决方案--------------------
如果传入参数都一致的话，$conn及其判断可以提到do...while前面