php 类静态变量 和 常量消耗内存及时间对比
在对类执行100w次循环后, 常量最快,变量其次,静态变量消耗时间最高
其中:
常量消耗:101.1739毫秒
变量消耗:2039.7689毫秒
静态变量消耗:4084.8911毫秒
测试代码:
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
class Timer_profiler { public static $begin_timer; public static $finish_timer; public static $timer_html; /** * 计算时间差 * @return type */ public static function getRecordTimer() { return (self::getFinishTimer() - self::getBeginTimer()) * 1000; } /** * 生成输出HTML * @param type $message * @return type */ public static function recordHtml($message = '') { self::setFinishTimer(); return "<p>{$message}耗时: " . self::getRecordTimer() . " 毫秒</p>"; } /** * 设置开始时间 */ public static function setBeginTimer() { self::$begin_timer = self::getTime(); } /** * 设置结束时间 */ public static function setFinishTimer() { self::$finish_timer = self::getTime(); } /** * 获取开始时间 * @return type */ public static function getBeginTimer() { return self::$begin_timer; } /** * 获取结束时间 * @return type */ public static function getFinishTimer() { return self::$finish_timer; } /** * 获取带微妙的时间戳 * @return type */ private static function getTime() { list($usec, $sec) = explode(" ", microtime()); return (number_format($sec+$usec,6,'.', '')); } } function computeTime($otime,$message){ return; $ntime = xdebug_time_index(); $str = ''; $str .= $message . ($ntime*1000-$otime*1000); $str .= "<br>"; echo $str; } function getMemoryUsed(){ $str = '消耗内存<h3 style="color:red"> '; $str .= round(memory_get_usage()/1024/1024, 4).'MB'; $str .= '</h3>'; echo $str; } $count_i = 100*10000; //$count_i = 100000; Timer_profiler::setBeginTimer(); computeTime(xdebug_time_index(),'开始执行'); echo Timer_profiler::recordHtml('开始执行'); getMemoryUsed(); class TestVar { public $A1 = 'aaaaaaaaaaaaaaaaa'; public $A2 = 'aaaaaaaaaaaaaaaaa'; public $A3 = 'aaaaaaaaaaaaaaaaa'; public $A4 = 'aaaaaaaaaaaaaaaaa'; public $A5 = 'aaaaaaaaaaaaaaaaa'; public $A6 = 'aaaaaaaaaaaaaaaaa'; public $A7 = 'aaaaaaaaaaaaaaaaa'; public $A8 = 'aaaaaaaaaaaaaaaaa'; } $TestVar = new TestVar(); for($i=0;$i<=$count_i;$i++){ $t = $TestVar->A1; $t = $TestVar->A2; $t = $TestVar->A3; $t = $TestVar->A4; $t = $TestVar->A5; $t = $TestVar->A6; $t = $TestVar->A7; $t = $TestVar->A8; } getMemoryUsed(); echo Timer_profiler::recordHtml('变量完成'); computeTime(xdebug_time_index(),'变量完成'); Timer_profiler::setBeginTimer(); class TestStaticVar { static $A1 = 'aaaaaaaaaaaaaaaaa'; static $A2 = 'aaaaaaaaaaaaaaaaa'; static $A3 = 'aaaaaaaaaaaaaaaaa'; static $A4 = 'aaaaaaaaaaaaaaaaa'; static $A5 = 'aaaaaaaaaaaaaaaaa'; static $A6 = 'aaaaaaaaaaaaaaaaa'; static $A7 = 'aaaaaaaaaaaaaaaaa'; static $A8 = 'aaaaaaaaaaaaaaaaa'; } for($i=0;$i<=$count_i;$i++){ $t = TestStaticVar::$A1; $t = TestStaticVar::$A2; $t = TestStaticVar::$A3; $t = TestStaticVar::$A4; $t = TestStaticVar::$A5; $t = TestStaticVar::$A6; $t = TestStaticVar::$A7; $t = TestStaticVar::$A8; } getMemoryUsed(); echo Timer_profiler::recordHtml('静态变量完成'); computeTime(xdebug_time_index(),'静态变量完成'); Timer_profiler::setBeginTimer(); class TestConstVar { const A1 = 'aaaaaaaaaaaaaaaaa'; const A2 = 'aaaaaaaaaaaaaaaaa'; const A3 = 'aaaaaaaaaaaaaaaaa'; const A4 = 'aaaaaaaaaaaaaaaaa'; const A5 = 'aaaaaaaaaaaaaaaaa'; const A6 = 'aaaaaaaaaaaaaaaaa'; const A7 = 'aaaaaaaaaaaaaaaaa'; const A8 = 'aaaaaaaaaaaaaaaaa'; } for($i=0;$i<=$count_i;$i++){ $t = TestConstVar::A1; $t = TestConstVar::A2; $t = TestConstVar::A3; $t = TestConstVar::A4; $t = TestConstVar::A5; $t = TestConstVar::A6; $t = TestConstVar::A7; $t = TestConstVar::A8; } getMemoryUsed(); echo Timer_profiler::recordHtml('常量完成'); computeTime(xdebug_time_index(),'常量完成'); //echo Timer_profiler::recordHtml('共执行'); computeTime(xdebug_time_index(),'共执行'); exit;