PHP uses caching to generate static pages

Http://www.cnblogs.com/lh460795/archive/2013/04/06/3003105.html

A stress test can be done at Apache/bin/ab.exe, which simulates multiple people and accesses a page concurrently.

The basic usage

Ab.exe–n 10000–c 10

-N indicates how many times the request

-C indicates how many people

If you want to test PHP's own caching mechanism, you need to configure it.

php.ini file

Display_errors=on

Output_buffering=off

error_reproting= Setting the error level

Looking at a piece of code, when using the cache, you can display text before sending the file header.

<?php

echo "YYY";

Header ("Content-type:text/htm;charset=utf-8");

echo "Hello";

?>

Several functions of PHP cache control:

1//php Cache control several functions: 2//Open cache [via PHP.ini, can also be on page Ob_start ()] 3 ob_start (); 4 echo "yyy"; 5 Header ("Content-type:text/htm;charset=utf-8"); 6 echo "Hello"; The 7//ob_clean function can empty the contents of the OutputBuffer. 8//ob_clean (); 9//ob_end_clean is to turn off the OB cache while emptying.//ob_clean ();//ob_end_flush () function is the memory output of the OB cache and closes ob12//ob_end_flush ();//ob_end_ The flush () function is the memory output of the OB cache, the//ob_flush () function is the output OB content, and is emptied, but not closed. Ob_flush ();         echo "KKK";//=>ob cache.//header ("Content-type:text/htm;charset=utf-8");//ob_get_contents () can get output_buffering content.//$contents =ob_get_ Contents ();//file_put_contents ("D:/log.text", $contents);

Let's look at an example, using caching technology, "if the cache file is not stored for more than 30 seconds, the cache file is taken directly":

 1 <?php 2 $id =$_get[' id ']; 3 $filename = "Static_id_". $id. ". HTML "; 4 $status =filemtime ($filename) +30>time ();//Determine if the file creation and modification time is longer than 30 seconds 5 if (File_exists ($fi                 Lename) && $status) {6 $str =file_get_contents ($filename); 7 echo $str; 8 }else{9 require_once "SqlHelper.class.php"; $sqlHelper =new Sqlhelp ER (); one $arr = $sqlHelper->execute_dql2 ("select * from News1 WHERE id= $id"); (Empty ($arr))                         {echo "Data is empty";}else{15/*** Cache starts ***/16                         Ob_start ();//The contents below will be stored in the buffer, and the contents will be stored in the buffer. Echo $arr [0][' Tile '];18 echo "<br/>", Echo $arr [0][' content '];20 $content = Ob_get_con            Tents ();//get content from the cache 21             Ob_end_clean ();//close cache and empty 22/*** cache End ***/23 File_put_contents ($                 FileName, $content), Echo $content 25}26}27 ?>

PHP uses caching to generate static pages