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关于php内存的分配。该如何处理

Jun 13, 2016 am 10:18 AM
memory php usage

关于php内存的分配。

$t = memory_get_usage();
// 3125000

$i = 1;
$a[$i] = $i;

$i = 1111111111;
$a[$i] = $i;

$i = '1';
$a[$i] = $i;

$i = '111111111111111111111111111';
$a[$i] = $i;


echo memory_get_usage()-$t;

?>

请问如何计算出各个占用了多少内存的。谢谢各位拉。

------解决方案--------------------
关注

ci1699 提的问题 都是好问题
------解决方案--------------------
逐次输出、观察

最好的方法是查看源码中是如何构造变量表的
------解决方案--------------------
php是基于c的,内存管理是不面向php的。
这种问题你要参考laruence大牛怎么说的。

http://www.laruence.com/2011/03/04/1894.html

http://www.laruence.com/2011/11/09/2277.html

------解决方案--------------------
你应该用memory_get_usage(TRUE)比较,如果都换成TRUE,我估计输出都是一样的

本质上,php有自己的内存管理机制,这样的需求就要求申请的时候,需要更大块内存

然后有一套自己应对内存管理结构,减少系统调用次数
------解决方案--------------------

探讨

引用:

php是基于c的,内存管理是不面向php的。
这种问题你要参考laruence大牛怎么说的。

http://www.laruence.com/2011/03/04/1894.html

http://www.laruence.com/2011/11/09/2277.html
说实在的,那些文章说的云山雾罩,点到为止。
……

------解决方案--------------------
我指的不是如何去申请内存的问题,而是他没有说明 php 是如何维护变量表的。
而 php 的变量应该是一个结构队列,每个每一项都应至少包括:变量名称、类型、值指针、是否是引用....
这才是我们需要关心的,而他是如何维护这张表的。却不是很重要
------解决方案--------------------
探讨

我指的不是如何去申请内存的问题,而是他没有说明 php 是如何维护变量表的。
而 php 的变量应该是一个结构队列,每个每一项都应至少包括:变量名称、类型、值指针、是否是引用....
这才是我们需要关心的,而他是如何维护这张表的。却不是很重要

------解决方案--------------------
多好的同学啊....


探讨

谢谢楼上各位大哥。
sina云什么有时候真慢。大半天打不开。


我还在折腾那排序。昨晚又搞到3点多=_=
想用php位图来排序,但耗太大内存。
现在想方法优化。晚点再贴代码上来。

------解决方案--------------------
前辈说,我们看看,受教了,谢了
------解决方案--------------------
laruence是去了php 核心開發的中國人吧
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