摘要：
Reason to use per-CPU variable1 Remember that the 2.6 kernel is preemptible; it would not do for a processor to be preempted inthe middle of a critical section that modifies a per-CPU variable.2 It also would not be good if your process were to be moved to another processor in the middle of a per-CP 阅读全文
摘要：
1 首先要说的最简单的是在一个process在运行的时候，它看到的内存是这个样子的。3G以后是给kernel使用的运行和动态分配的内存的空间，注意因为是process所看到的，下面全部都是虚拟地址空间。如下：2 然后需要说的是Linux Physical Memory Layout下面这段话解释了为什么linux不能占用所有的Ram内存：Why isn't the kernel loaded starting with the first available megabyte of RAM? Well, the PC architecture hasseveral peculiarit 阅读全文