Encontrando o número de núcleos na minha CPU no GNU / Linux

0

Quando eu faço cat /proc/cpuinfo , obtenho as seguintes informações impressas abaixo. Posso concluir desta informação que existem 8 núcleos na minha máquina? Estou interessado em fazer alguma programação paralela usando o OpenMP, que deve usar todos os núcleos da CPU para fazer alguns cálculos.

Existem 8 desses processadores listados nas informações (que eu suponho que sejam núcleos). Mas eu estou confuso porque existe um campo em cada bloco que diz cpu cores 4 .

processor   : 0
vendor_id   : GenuineIntel
cpu family  : 6
model       : 26
model name  : Intel(R) Core(TM) i7 CPU         960  @ 3.20GHz
stepping    : 5
cpu MHz     : 1600.000
cache size  : 8192 KB
physical id : 0
siblings    : 8
core id     : 0
cpu cores   : 4
apicid      : 0
initial apicid  : 0
fpu     : yes
fpu_exception   : yes
cpuid level : 11
wp      : yes
flags       : 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 rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 popcnt lahf_lm ida dts tpr_shadow vnmi flexpriority ept vpid
bogomips    : 6415.99
clflush size    : 64
cache_alignment : 64
address sizes   : 36 bits physical, 48 bits virtual
power management:

processor   : 1
vendor_id   : GenuineIntel
cpu family  : 6
model       : 26
model name  : Intel(R) Core(TM) i7 CPU         960  @ 3.20GHz
stepping    : 5
cpu MHz     : 1600.000
cache size  : 8192 KB
physical id : 0
siblings    : 8
core id     : 1
cpu cores   : 4
apicid      : 2
initial apicid  : 2
fpu     : yes
fpu_exception   : yes
cpuid level : 11
wp      : yes
flags       : 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 rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 popcnt lahf_lm ida dts tpr_shadow vnmi flexpriority ept vpid
bogomips    : 6415.95
clflush size    : 64
cache_alignment : 64
address sizes   : 36 bits physical, 48 bits virtual
power management:

processor   : 2
vendor_id   : GenuineIntel
cpu family  : 6
model       : 26
model name  : Intel(R) Core(TM) i7 CPU         960  @ 3.20GHz
stepping    : 5
cpu MHz     : 1600.000
cache size  : 8192 KB
physical id : 0
siblings    : 8
core id     : 2
cpu cores   : 4
apicid      : 4
initial apicid  : 4
fpu     : yes
fpu_exception   : yes
cpuid level : 11
wp      : yes
flags       : 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 rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 popcnt lahf_lm ida dts tpr_shadow vnmi flexpriority ept vpid
bogomips    : 6415.91
clflush size    : 64
cache_alignment : 64
address sizes   : 36 bits physical, 48 bits virtual
power management:

processor   : 3
vendor_id   : GenuineIntel
cpu family  : 6
model       : 26
model name  : Intel(R) Core(TM) i7 CPU         960  @ 3.20GHz
stepping    : 5
cpu MHz     : 1600.000
cache size  : 8192 KB
physical id : 0
siblings    : 8
core id     : 3
cpu cores   : 4
apicid      : 6
initial apicid  : 6
fpu     : yes
fpu_exception   : yes
cpuid level : 11
wp      : yes
flags       : 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 rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 popcnt lahf_lm ida dts tpr_shadow vnmi flexpriority ept vpid
bogomips    : 6415.93
clflush size    : 64
cache_alignment : 64
address sizes   : 36 bits physical, 48 bits virtual
power management:

processor   : 4
vendor_id   : GenuineIntel
cpu family  : 6
model       : 26
model name  : Intel(R) Core(TM) i7 CPU         960  @ 3.20GHz
stepping    : 5
cpu MHz     : 1600.000
cache size  : 8192 KB
physical id : 0
siblings    : 8
core id     : 0
cpu cores   : 4
apicid      : 1
initial apicid  : 1
fpu     : yes
fpu_exception   : yes
cpuid level : 11
wp      : yes
flags       : 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 rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 popcnt lahf_lm ida dts tpr_shadow vnmi flexpriority ept vpid
bogomips    : 6415.91
clflush size    : 64
cache_alignment : 64
address sizes   : 36 bits physical, 48 bits virtual
power management:

processor   : 5
vendor_id   : GenuineIntel
cpu family  : 6
model       : 26
model name  : Intel(R) Core(TM) i7 CPU         960  @ 3.20GHz
stepping    : 5
cpu MHz     : 1600.000
cache size  : 8192 KB
physical id : 0
siblings    : 8
core id     : 1
cpu cores   : 4
apicid      : 3
initial apicid  : 3
fpu     : yes
fpu_exception   : yes
cpuid level : 11
wp      : yes
flags       : 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 rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 popcnt lahf_lm ida dts tpr_shadow vnmi flexpriority ept vpid
bogomips    : 6415.91
clflush size    : 64
cache_alignment : 64
address sizes   : 36 bits physical, 48 bits virtual
power management:

processor   : 6
vendor_id   : GenuineIntel
cpu family  : 6
model       : 26
model name  : Intel(R) Core(TM) i7 CPU         960  @ 3.20GHz
stepping    : 5
cpu MHz     : 1600.000
cache size  : 8192 KB
physical id : 0
siblings    : 8
core id     : 2
cpu cores   : 4
apicid      : 5
initial apicid  : 5
fpu     : yes
fpu_exception   : yes
cpuid level : 11
wp      : yes
flags       : 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 rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 popcnt lahf_lm ida dts tpr_shadow vnmi flexpriority ept vpid
bogomips    : 6415.91
clflush size    : 64
cache_alignment : 64
address sizes   : 36 bits physical, 48 bits virtual
power management:

processor   : 7
vendor_id   : GenuineIntel
cpu family  : 6
model       : 26
model name  : Intel(R) Core(TM) i7 CPU         960  @ 3.20GHz
stepping    : 5
cpu MHz     : 1600.000
cache size  : 8192 KB
physical id : 0
siblings    : 8
c    ore id     : 3
cpu cores   : 4
apicid      : 7
initial apicid  : 7
fpu     : yes
fpu_exception   : yes
cpuid level : 11
wp      : yes
flags       : 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 rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 popcnt lahf_lm ida dts tpr_shadow vnmi flexpriority ept vpid
bogomips    : 6415.91
clflush size    : 64
cache_alignment : 64
address sizes   : 36 bits physical, 48 bits virtual
power management:
    
por smilingbuddha 30.01.2012 / 18:29

2 respostas

2

Puramente por causa do OpenMP yes, você pode seguramente assumir que você tem 8 threads disponíveis. No entanto, realisticamente, você deveria estar lendo a linha

cpu cores : 4

Em cada informação do núcleo da CPU. O motivo pelo qual você está vendo 8 processadores é que você tem um CPU Quad Code com Hyper Threading. ou seja, 4 x 2 = 8 Threads.

    
por 30.01.2012 / 18:35
2

Um i7 960 possui 4 núcleos. Existem 8 threads, porque cada núcleo é hyper threaded. Mas apenas 4 núcleos físicos. 8 núcleos virtuais.

Mais detalhes sobre esse processador aqui:

link

    
por 30.01.2012 / 18:34