optimizing php code for less php processing - php

Question

I am having some problem with my apache server when handling big amount of traffic. after some optimizations I did. I still have the same problem. I check my log file and it turned out that I have a lot of php processing. The following code is getting processed about 800 times a minute (when I have high traffic) and casing my server to crash.
1) is there any parts of the code that I need to rewrite that would make it take less php processing ?
2) is it a good idea to have all of this code before the html starts ?
<?php
$ip = $_SERVER['REMOTE_ADDR'];
mysql_connect('', '', '');
mysql_select_db('');
if(empty($_GET['i']) == false){
$get_image = mysql_real_escape_string($_GET['i']);
$check_if_image = mysql_query("SELECT `id`, `image_name`, `image_type`, `image_caption`, `image_voteup`, `image_votedown`, `image_views`, `fb_userid` FROM images_new WHERE image_name = '$get_image'");
if(mysql_num_rows($check_if_image) == 1){
$result = mysql_fetch_assoc($check_if_image);
$image_id = $result['id'];
$image_name = $result['image_name'];
$image_type = $result['image_type'];
$image_caption = stripslashes($result['image_caption']);
$image_voteup = $result['image_voteup'];
$image_votedown = $result['image_votedown'];
//$image_date = $result['image_date'];
$image_views = $result['image_views'];
$fb_username = $result['fb_username'];
$fb_userid = $result['fb_userid'];
//next image
$next_image_id = $image_id + 1;
$check_next_image = mysql_query("SELECT `image_name` FROM images_new WHERE id = '$next_image_id'");
if(mysql_num_rows($check_next_image) == 1){
$next_image_result = mysql_fetch_assoc($check_next_image);
$next_image_name = $next_image_result['image_name'];
}
// pre image
$pre_image_id = $image_id - 1;
$check_pre_image = mysql_query("SELECT `image_name` FROM images_new WHERE id = '$pre_image_id'");
if(mysql_num_rows($check_pre_image) == 1){
$pre_image_result = mysql_fetch_assoc($check_pre_image);
$pre_image_name = $pre_image_result['image_name'];
}
//shares, comments, and likes
$fb_page_url = "http://www.xxx.com/images.php?i=".$get_image;
$fb_url = "http://api.facebook.com/restserver.php?method=links.getStats&urls=".urlencode($fb_page_url);
$fb_xml = file_get_contents($fb_url);
$fb_xml = simplexml_load_string($fb_xml);
$fb_shares = $fb_xml->link_stat->share_count;
$fb_likes = $fb_xml->link_stat->like_count;
$fb_likes_and_shares = $fb_likes + $fb_shares;
$fb_comments = $fb_xml->link_stat->commentsbox_count;
//facebook
require_once('scripts/facebook.php');
$config = array('appId' => '','secret' => '');
$params = array('scope'=>'user_likes,publish_actions,email,offline_access,user_birthday');
$facebook = new Facebook($config);
$user = $facebook->getUser();
if($user){
try{
$user_profile = $facebook->api('/me','GET');
$user_id = $user_profile['username'];
$expire_time = time() + 30758400;
//insert cookie id
if (!isset($_COOKIE['id'])){
$cookie_id = $user_profile['username'];
setcookie("id", $cookie_id, $expire_time, '/');
}
//insert cookie name
if (!isset($_COOKIE['name'])){
$user_name = $user_profile['first_name'];
setcookie("name", $user_name, $expire_time, '/');
}
//check if the user like the fan page
$isFan = $facebook->api(array(
"method" => "pages.isFan",
"page_id" => ''
));
}catch(FacebookApiException $e) {
error_log($e->getType());
error_log($e->getMessage());
}
}else{//if no user
if(isset($_COOKIE['name'])){
$user_name = $user_profile['first_name'];
setcookie("name", $user_name, time() - 30758400, '/');
}
}
//increase views
if($facebook->getUser()){
mysql_query("UPDATE images_main SET image_views = image_views + 1 WHERE image_name='$image_name'");
mysql_query("UPDATE images_new SET image_views = image_views + 1 WHERE image_name='$image_name'");
}
}else{//image was not found in the database.
header('Location: index.php');
}
}else{//redirect if get is empty
header('Location: index.php');
}
?>

Answer 1

I would say the key factor is your call to the Facebook API, such things are always expensive and easily cacheable, put that code in a separate page/include and cache it as you like.
Also as a side note, you should consider reducing the number of db queries and you may wish to update your db driver... as invariably everyone points out #Madara Uchiha

Answer 2

I see a few items right off the bat.
First query:
$check_if_image = mysql_query("SELECT `id`, `image_name`, `image_type`, `image_caption`, `image_voteup`, `image_votedown`, `image_views`, `fb_userid` FROM images_new WHERE image_name = '$get_image'");
If you only need one result back, put a 'LIMIT 1' at then end (unless this field has a UNIQUE index, in which case this shouldn't matter). Also make sure this field is indexed and preferably a VARCHAR field instead of TEXT or BLOB.
Next, you are running 2 queries to get the previous and next images. I would combine this into 1 query like this:
SELECT `image_name` FROM images_new WHERE id IN ('$next_image_id', '$pre_image_id')
Also, you can apply the first optimization I mentioned to these 2 queries:
if($facebook->getUser()){
mysql_query("UPDATE images_main SET image_views = image_views + 1 WHERE image_name='$image_name'");
mysql_query("UPDATE images_new SET image_views = image_views + 1 WHERE image_name='$image_name'");
}
Lastly, going through the Facebook API is going to add load time that you cannot do much about. Hopefully this gets you started down the right path.