[体系结构][CPU]32位机只能寻址4 GB内存吗？

soloforce

讨论背景话题：
谈谈大内存的swap的分区方法
http://bbs.linuxsir.cn/showthrea ... mp;page=1&pp=15
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大家就此话题讨论讨论 ， 澄清一些认识
(对事不对人哦！)

Yuri

编译过内核的都知道,在内存选项里有一个选单就是支持4G以上的内存.没看见么?

Yuri

你不编译64为支持,选上4G大内存支持试试

zhllg

http://en.wikipedia.org/wiki/PAE

lollipop

当前PC机用的是三总线结构，寻址范围与地址总线的位数有关。
哪位来详细介绍一下PAE是怎么在32位的情况下来实现64G的寻址的？
好像还是要硬件支持的，这样或许不是纯32位了吧。

The processor hardware is augmented with additional address lines used to select the additional memory, and 36 bit page tables, but regular application software continues to use instructions with 32 bit addresses and a flat memory model limited to 4 gigabytes. The operating system uses PAE to map this 32 bit address space onto the 64 gigabytes of total memory, and the map can be and usually is different for each process. In this way the extra memory is useful even though regular applications cannot access it all simultaneously.

bbbush

Post by zhllg
http://en.wikipedia.org/wiki/PAE

wikipedia 怎么什么都有啊...

Yuri

这是维基百科,一个网络上的免费自由的百科全书.去年在上面混了好长一段时间.上面中国大陆北京地区通讯录里可以找到我.
上面你随便搜一个东西命中率N高

lollipop

我也想去上面贡献点东西，NND，说我提交的东西涉及侵犯知识产权，全给删了，于是，再也不去了
//跑题了，各位

peter_huang

The processor hardware is augmented with additional address lines used to select the additional memory, and 36 bit page tables.

呵呵，硬件的寻址能力是前提。