Detailed introduction to php performance optimization

PHP is a very popular scripting language. Now many companies (Sina, Youku, Baidu, Sohu, Taobao, etc.) are using this language for website development. With this article, I just hope to improve the performance of your php scripts. Please remember that the performance of your PHP scripts often depends on your PHP version, your web server environment and the complexity of your code.

Optimize bottlenecks in your code

Hoare once said that "premature optimization is the root of all misfortune." When you want to make your website run faster, you should do optimization. What do you need to do before you change your code? What is causing the system to be slow? You can optimize your php through the following guidance and other methods, which may be database reasons or network reasons! By optimizing your php code, you can try to find out the bottlenecks of your system.

Upgrade your PHP version

Your team members suggested that the PHP engine has had many symbolic performance improvements over the years. If your web server is still running an older version, such as php3 or php4. So before you try to optimize your code, you should do a deep dive into the upgrades between versions.

Use caching

Use caching module (such as Memcache) or template system (such as Smarty) for caching processing. We can cache data library results and extract page results to improve website performance.

Use Output Buffer

When your script tries to render, PHP will use the memory buffer to save all data. Caching may make your page appear slow because the buffer is filled with all the data to be responded to before the result is returned to the user. Fortunately, you can make a change that forces PHP to respond to the user before the buffer fills up, which will make your website look faster.

• Output Cache Control

Avoid writing naive setters and getters

When you write PHP classes, you can Directly manipulate objectproperties, which can help you save time and improve the performance of your scripts. Rather than the kind of setters and getters that make people feel childish and ridiculous.

The following are some cases: the dog class operates the name attribute by using setName() and getName().

class dog {
  public $name = '';

  public function setName($name) {
    $this->name = $name;
  }

  public function getName() {
    return $this->name;
  }
}

Note: setName() and getName() do no work except storing and returning the name attribute.

$rover = new dog();
$rover->setName('rover');
echo $rover->getName();

Directly setting and accessing the name attribute can improve performance by 100% and reduce development time!

$rover = new dog();
$rover->name = 'rover';
echo $rover->name;

There is no reason not to copy variables

Sometimes junior phpers, in order to make the code more "clean", often reassign the defined variable to another variable. This effectively results in double memory consumption (when changing variables), which causes the performance of the script to decrease. For example, if a user inserts a 512KB variable into another variable, 1MB of memory will be consumed.

$description = strip_tags($_POST['description']);
echo $description;

The above code copies the variables for no reason. You only need to simply output variables inline without consuming additional memory.

echo strip_tags($_POST['description']);

Avoid looping SQL operations

A common mistake is to place a SQL operation in a loop, which results in frequent database accesses. More importantly, this will directly cause The performance of the script is poor. In the following example, you can reset a loop operation to a single SQL statement.

foreach ($userList as $user) {
  $query = 'INSERT INTO users (first_name,last_name) VALUES("' . $user['first_name'] . '", "' . $user['last_name'] . '")';
  mysql_query($query);
}

Process:

INSERT INTO users (first_name,last_name) VALUES("John", "Doe")

Instead of this looping scheme, you can splice the data into a single database operation.

$userData = array();
foreach ($userList as $user) {
    $userData[] = '("' . $user['first_name'] . '", "' . $user['last_name'] . '")';
 }
$query = 'INSERT INTO users (first_name,last_name) VALUES' . implode(',', $userData);
mysql_query($query);

Process:

INSERT INTO users (first_name,last_name) VALUES("John", "Doe"),("Jane", "Doe")...

• MySQL INSERT Syntax

Summary

PHP performance optimization There are many more. If you have a deeper understanding of this aspect, you can discuss it together. I will also put your good suggestions into the blog post for other PHPers to refer to. As a phper, it is a very proud thing to be able to improve the capabilities of many phper

. ——Many people regard PHP as a grassroots language. I personally hope that the PHP language can go further in the future, so that the money in the hands of a PHPer will be more and more!

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