Red Hat Enterprise Linux 5 Administration Unleashed

200CHAPTER 864-Bit, Multi-Core, and Hyper-Threading Technology ProcessorsLISTING 8.1Continuedflags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca \cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext lm 3dnowext \3dnow pnibogomips : 3214.42TLB size : 1088 4K pagesclflush size : 64cache_alignment : 64address sizes : 40 bits physical, 48 bits virtualpower management: ts ttpProcessors with Hyper-Threading TechnologyProcessors with Hyper-Threading Technology (HT Technology) are seen by the operatingsystem as two logical processors. These processors are different from multi-core processorsbecause processors with HT Technology do not contain all the components of two separateprocessors. Only specific parts of a second processor are included so that two processthreads can be executed at the same time.When Red Hat Enterprise Linux detects a processor with HT Technology, it configures thesystem as a multi-processor system, and therefore uses the SMP kernel. This can be seen inthe output of the /proc/cpuinfo virtual file as shown in Listing 8.2.LISTING 8.2Contents of /proc/cpuinfo for a Process with HT Technologyprocessor : 0vendor_id : GenuineIntelcpu family : 15model : 3model name : Genuine Intel(R) CPU 3.20GHzstepping : 3cpu Mhz : 2793.829cache size : 1024 KBphysical id : 0siblings : 2core id : 0cpu cores : 1fdiv_bug : nohlt_bug: nof00f_bug : nocoma_bug : nofpu: yesfpu_exception : yescpuid level : 5wp: yesflags: fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca