cpu core
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Physical CPU
Number of CPUs on Slots in Actual Server
The number of physical cpu can be counted as the number of non-repeating physical id
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Logical CPU
In general, we think that a cpu can have multiple cores, and with intel’s Hyper-Threading Technology (HT), it can logically split the number of cpu core by a factor of two.
Logical cpu Count = Physical CPU Count x cpu cores This specification value x 2 (if ht is supported and turned on)
Note: the number of CPUs viewed by top under Linux is also the number of logical CPUs
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CPU cores
The number of chipsets capable of processing data on a CPU, such as the current i5 760, is a dual-core four-thread CPU, while i5250 is a four-core four-thread CPU.
In general, the number of physical CPUs × the number of cores per core should be equal to the number of logical CPUs, if not equal, then the server’s CPU supports hyper-threading technology
sysctl hw
sysctl hw.physicalcpu
sysctl hw.logicalcpu
Separate output
hw.physicalcpu: 2
hw.logicalcpu: 4
system_profiler SPHardwareDataType
Hardware:
Hardware Overview:
Model Name: MacBook Air
Model Identifier: MacBookAir7,2
Processor Name: Intel Core i7
Processor Speed: 2.2 GHz
Number of Processors: 1
Total Number of Cores: 2
L2 Cache (per Core): 256 KB
L3 Cache: 4 MB
Memory: 8 GB
Boot ROM Version: xxxxxxx
SMC Version (system): 2.27f2
Serial Number (system): xxxxxxx
Hardware UUID: xxxxxxxxxxxxxxx