CPU

From Linuxintro
Revision as of 03:34, 23 January 2012 by imported>ThorstenStaerk (→‎Load average)

CPU (Central Processing Unit)s consist of logic circuitry that interprets and executes the software instructions that drive a computer. For more information, see http://en.wikipedia.org/wiki/Cpu

What CPUs do I have?

To find out what CPUs you have at what speed, open a console and call hwinfo, e.g.:

$ hwinfo --cpu
01: None 00.0: 10103 CPU
  [Created at cpu.301]
  Unique ID: rdCR.j8NaKXDZtZ6
  Hardware Class: cpu
  Arch: X86-64
  Vendor: "GenuineIntel"
  Model: 6.15.11 "Intel(R) Core(TM)2 Quad CPU    Q6600  @ 2.40GHz"
  Features: fpu,vme,de,pse,tsc,msr,pae,mce,cx8,apic,sep,mtrr,pge,mca,cmov,pat,pse36,clflush,dts,acpi,mmx,fxsr,sse,sse2,ss,ht,tm,pbe,syscall,nx,lm,constant_tsc,arch_perfmon,pebs,bts,rep_good,pni,monitor,ds_cpl,vmx,est,tm2,ssse3,cx16,xtpr,lahf_lm
  Clock: 1600 MHz
  BogoMips: 4791.54
  Cache: 4096 kb
  Units/Processor: 4
  Config Status: cfg=new, avail=yes, need=no, active=unknown

The block in this example is repeated 4 times because there this is a quad-core processor (Units/Processor: 4). The "clock" value is different because this is a 2.40GHz processor, running at 1600 MHz.

To reduce complexity:

$ hwinfo --cpu --short
cpu:
                       Intel(R) Core(TM)2 Quad CPU    Q6600  @ 2.40GHz, 1600MHz
                       Intel(R) Core(TM)2 Quad CPU    Q6600  @ 2.40GHz, 1600MHz
                       Intel(R) Core(TM)2 Quad CPU    Q6600  @ 2.40GHz, 1600MHz
                       Intel(R) Core(TM)2 Quad CPU    Q6600  @ 2.40GHz, 1600MHz

tells me I have a quad-core processor and 4 processor cores, so one processor with 4 cores, 2.4GHz ones running at 1600MHz.

Load average

load average is a measure to tell how busy the CPU is. load average shows the average number of processes waiting for execution. Usually there are three numbers presented where the first show average last minute, second average for last five minutes and the third show average load for the last fifteen minutes.

Show your computer's load average with the commands uptime or top.

See also

  • top - what does your CPU do
  • diagnostics - what is your hardware and what does it do