- 论坛徽章:
- 0
|
原帖由 drowndog 于 2010-1-7 09:30 发表 ![]()
SMP的服务器，一般在每个核心内部，都会集成一个内存控制器，因此，访问内存的带宽远远大于单个CPU时的带宽。
另外，你说的缓存也是一个因素，但更重要的是二级缓存。一级缓存的容量太小（指令缓存和数据缓存一 ...
按照ULK的说法，SMP环境下的内存访问也是严格串行的：
In multiprocessor systems, all CPUs usually share the same memory; this
means that RAM chips may be accessed concurrently by independent CPUs.
Because read or write operations on a RAM chip must be performed serially,
a hardware circuit called a memory arbiter is inserted between the bus and
every RAM chip. Its role is to grant access to a CPU if the chip is free
and to delay it if the chip is busy servicing a request by another processor.
... ...
----from《Understanding the Linux Kernel, 3rd Edition》：2.1. Memory Addresses |
|
免费注册
发表于 2010-01-07 09:07
发表于 2010-01-07 11:17
