网站需要新加一个常量,打开了本地的config.php文件,想到了几年前测试过的hidef以及apc提升define性能的方案。
我的程序中有对开发、测试、生产服务器分别做了不同的配置,在常量方面则使用了一个数组定义了所有需要定义的常量,然后检测是否有apc_load_constants函数,没有的话,批量define。使用apc时,每增加一个常量,还需要修改一下$key才能生效。
而现在测试、生产服务器php都升级到5.4后,opcode缓存就使用了Zend opcache,不再安装APC。因为有用到apc user cache,因此额外装了apcu,和apc用法一模样,完全不用改程序。而apcu不支持apc_load_constants和apc_define_constants,因此apc这个方案就无法用了。去官网装了最新版hidef 0.1.13,2012-7-12发布的stable,一年多了。
写了个简单程序测试define化的时间,大概运行1000次需要2.8ms。那么对于一个中型网站(例如一天php运行1000w次)来说,如果每页定义25个常量,大概每天需要化 10000000*25/1000*2.8=700000ms,就是700秒。差不多使用hidef可以一天节省700s的PHP运行时间。
再看看读的性能好了,测试读1w次一个常量,值都是1,分别是37ms和0.7ms。那么如果一天1000w次,每页平均使用20个常量,则需要740秒,而使用hidef是14秒,好吧,又一个700多秒。
一天省1400秒php运行时间,也许是还是微不足道,但总是好的,也是值的尝试的,毕竟define的参数变化的机率非常少。
当define参数需要修改时,修改配置文件,然后重载下php-fpm,就好了。
hidef具体安装方法参见:提高define性能的php扩展hidef的安装和使用
在百度里搜索“hidef”,排第3位的是一个copy我博文的网站:( 而我自己发布的提高define性能的php扩展hidef的安装和使用在前三页没有找到。显然是百度对原创的识别出了些偏差。
百度搜索“hidef php”,那个网址排第一,第二是官网,我的在第三。
gg搜索“hidef php”,第一官网,第3是另一篇原创,我的在第四。gg的识别就不错!
360搜索"hidef php",第一那个copy站,第二我的,第三另一篇原创。
因此有了这篇的诞生,看看能不能帮第一篇排上去或者这篇排上去也行。
附原配置常量的程序示例代码:
if (function_exists('apc_load_constants')) {
function define_array($key, $arr, $case_sensitive = false) {
if (!apc_load_constants($key, $case_sensitive)) {
apc_define_constants($key, $arr, $case_sensitive);
}
}
} else {
function define_array($key, $arr, $case_sensitive = false) {
foreach ($arr as $name => $value) {
define($name, $value, $case_sensitive);
}
}
}
$constants = array(
'HX' => 1,
'BLOG_URL' => 'http://www.jb51.net/',
'WWW_URL' => 'http://www.jb51.net/',
);
define_array('hx_defined',$constants);
附测试define速度的代码。
$t1 = microtime(1);
$constants = array(
'hx1' => 1,
'hx2' => '2',
'hx3' => '3',
'hx4' => '4',
'hx5' => '5',
'hx6' => '6',
'hx7' => '7',
'hx8' => '8',
'hx9' => '9',
'hx10' => '10',
);
function define_array($key, $arr) {
foreach ($arr as $name => $value) {
define($name.$i, $value);
}
}
for($i=0;$i
define_array($i,$constants);
}
$t2 = microtime(1);
echo ($t2-$t1)*1000;
//读性能
$t1 = microtime(1);
for($i=0;$i
$t = hx1;
}
$t2 = microtime(1);
echo ' '.($t2-$t1)*1000;
$t1 = microtime(1);
for($i=0;$i
$t = HX;
}
$t2 = microtime(1);
echo ' '.($t2-$t1)*1000;

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