CPU拓扑结构的调查

原作者：http://www.verydemo.com/demo_c167_i201201.html

CPU拓扑结构的调查

在做多核程序的时候(比如Erlang程序)，我们需要了解cpu的拓扑结构, 了解logic CPU和物理的CPU的映射关系，以及了解CPU的内部的硬件参数，比如说

L1，L2 cache的大小等信息。

Linux下的/proc/cpuinfo提供了相应的信息，但是比较不全面。 /sys/devices/system/cpu/也提供了topology结构但是比较难解读。

很多时候我们需要更专业的工具了。intel提供了这样的救助。参见： http://software.intel.com/en-us/articles/intel-64-architecture-processor-topology-enumeration/
下载下来编译执行就好。

[admin@my174 cpu-topology]$ ./cpu_topology64.out

Advisory to Users on system topology enumeration

This utility is for demonstration purpose only. It assumes the hardware topology

configuration within a coherent domain does not change during the life of an OS

session. If an OS support advanced features that can change hardware topology

configurations, more sophisticated adaptation may be necessary to account for

the hardware configuration change that might have added and reduced the number

of logical processors being managed by the OS.

User should also`be aware that the system topology enumeration algorithm is

based on the assumption that CPUID instruction will return raw data reflecting

the native hardware configuration. When an application runs inside a virtual

machine hosted by a Virtu…………………………………………………………………………