对/proc/cpuinfo文件下的各个参数的说明及实践

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我们通常要检查系统的cpu的相关信息,之前在进行查看cpu的信息的时候,我最长用的方式是,直接将/etc/cpuinfo下的所有的内容进行显示,然后通过对全部文件的查看,来提取我们需要的信息,虽然查看过这方面的信息,但是对于这个文件中的内容了解的还是不够详细,今天看到了一篇文章写的不错,作为一个笔记,拿过来借鉴学习,并作为一个积累。

以上输出项的含义如下:———>>>>>原博客地址 :

http://blog.csdn.net/lgstudyvc/article/details/7889364

processor :系统中逻辑处理核的编号。对于单核处理器,则课认为是其CPU编号,对于多核处理器则可以是物理核、或者使用超线程技术虚拟的逻辑核

vendor_id :CPU制造商

cpu family :CPU产品系列代号

model   :CPU属于其系列中的哪一代的代号

model name:CPU属于的名字及其编号、标称主频

stepping   :CPU属于制作更新版本

cpu MHz   :CPU的实际使用主频

cache size   :CPU二级缓存大小

physical id   :单个CPU的标号

siblings       :单个CPU逻辑物理核数

core id        :当前物理核在其所处CPU中的编号,这个编号不一定连续

cpu cores    :该逻辑核所处CPU的物理核数

apicid          :用来区分不同逻辑核的编号,系统中每个逻辑核的此编号必然不同,此编号不一定连续

fpu             :是否具有浮点运算单元(Floating Point Unit)

fpu_exception  :是否支持浮点计算异常

cpuid level   :执行cpuid指令前,eax寄存器中的值,根据不同的值

cpuid

指令会返回不同的内容

wp             :表明当前CPU是否在内核态支持对用户空间的写保护(Write Protection)

flags          :当前CPU支持的功能


bogomips

:在系统内核启动时粗略测算的CPU速度(Million Instructions Per Second)

clflush size  :每次刷新缓存的大小单位

cache_alignment :缓存地址对齐单位

address sizes     :可访问地址空间位数

power management :对能源管理的支持,有以下几个可选支持功能:

ts:  temperature sensor

fid:   frequency id control

vid:  voltage id control

ttp:  thermal trip

tm:

stc:

100mhzsteps:

hwpstate:

CPU信息中flags各项含义:

fpu: Onboard (x87) Floating Point Unit

vme: Virtual Mode Extension

de: Debugging Extensions

pse: Page Size Extensions

tsc: Time Stamp Counter: support for RDTSC and WRTSC instructions

msr: Model-Specific Registers

pae: Physical Address Extensions: ability to access 64GB of memory; only 4GB can be accessed at a time though

mce: Machine Check Architecture

cx8: CMPXCHG8 instruction

apic: Onboard Advanced Programmable Interrupt Controller

sep: Sysenter/Sysexit Instructions; SYSENTER is used for jumps to kernel memory during system calls, and SYSEXIT is used for jumps: back to the user code

mtrr: Memory Type Range Registers

pge: Page Global Enable

mca: Machine Check Architecture

cmov: CMOV instruction

pat: Page Attribute Table

pse36: 36-bit Page Size Extensions: allows to map 4 MB pages into the first 64GB RAM, used with PSE.

pn: Processor Serial-Number; only available on Pentium 3

clflush: CLFLUSH instruction

dtes: Debug Trace Store

acpi: ACPI via MSR

mmx: MultiMedia Extension

fxsr: FXSAVE and FXSTOR instructions

sse: Streaming SIMD Extensions. Single instruction multiple data. Lets you do a bunch of the same operation on different pieces of input: in a single clock tick.

sse2: Streaming SIMD Extensions-2. More of the same.

selfsnoop: CPU self snoop

acc: Automatic Clock Control

IA64: IA-64 processor Itanium.

ht: HyperThreading. Introduces an imaginary second processor that doesn’t do much but lets you run threads in the same process a  bit quicker.

nx: No Execute bit. Prevents arbitrary code running via buffer overflows.

pni: Prescott New Instructions aka. SSE3

vmx: Intel Vanderpool hardware virtualization technology

svm: AMD “Pacifica” hardware virtualization technology

lm: “Long Mode,” which means the chip supports the AMD64 instruction set

tm: “Thermal Monitor” Thermal throttling with IDLE instructions. Usually hardware controlled in response to CPU temperature.

tm2: “Thermal Monitor 2″ Decrease speed by reducing multipler and vcore.

est: “Enhanced SpeedStep”

根据以上内容,我们则可以很方便的知道当前系统关于CPU、CPU的核数、CPU是否启用超线程等信息。

查询系统具有多少个逻辑核:

cat /proc/cpuinfo | grep "processor" | wc -l

查询系统CPU的物理核数:

cat /proc/cpuinfo | grep "cpu cores" | uniq

查询系统CPU是否启用超线程:

cat /proc/cpuinfo | grep -e "cpu cores"  -e "siblings" | sort | uniq

输出举例:

cpu cores    : 6

siblings     : 6

如果cpu cores数量和siblings数量一致,则没有启用超线程,否则超线程被启用。

查询系统CPU的个数:cat /proc/cpuinfo | grep “physical id” | sort | uniq | wc -l


以上为原博客中所提到的,下面进行我的补充,作为自己学习的拓展:

 cat /proc/cpuinfo |grep flags | grep ' lm ' | wc -l  //结果大于0, 说明支持64位计算。lm指long mode, 支持lm则是64位<span style="color:#FF0000;"></span>

<span style="color:#FF0000;">cat/proc/cpuinfo | grep name | cut –f 2 –d : | uniq -c  //查看CPU型号</span>

<span style="color:#FF0000;"># cat /proc/cpuinfo |grep physical | uniq -c  //查看实际有几颗CPU</span>

<span style="color:#FF0000;">#  egrep --color "lm|svm|vmx" /proc/cpuinfo //进行查看cpu是否支持硬件虚拟化</span>

查询系统CPU是否支持某项功能,则根以上类似,输出结果进行sort, uniq和grep就可以得到结果

后续如果有对这方面的补充,会继续添加相关内容进行总结