"Linux command" Lscpu,, Etc/cpuinfo detailed

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i2000:~ # lscpuArchitecture:          x86_64CPU op-mode(s):        32-bit, 64-bitByte Order:            Little EndianCPU(s):                8On-line CPU(s) list:   0-7Thread(s) per core:    2Core(s) per socket:    1Socket(s):             4NUMA node(s):          1Vendor ID:             GenuineIntelCPU family:            6Model:                 62Stepping:              4CPU MHz:               2499.998BogoMIPS:              4999.99Hypervisor vendor:     KVMVirtualization type:   fullL1d cache:             32KL1i cache:             32KL2 cache:              4096KNUMA node0 CPU(s):     0-7

　　

The socket is the number of slots on the motherboard that are plugged into the CPU, which is the number of physical CPUs that can be plugged in.

Core is what we usually call "nuclear", each physical CPU can be dual-core, quad-core and so on.

Thread is the number of hardware threads per core, that is, Hyper-threading

Enter the command cat/proc/cpuinfo view physical ID There are several, the above results show only 0, so there is only one physical CPU; There are several processor, the above results show 0 and 12, so there are two logical CPUs.

(i) Concept
① Physical CPU
Number of CPUs on the actual server slots
Number of physical CPUs, number of physical IDs that can be repeated
② Logical CPU
/proc/cpuinfo used to store CPU hardware information.
The information content lists the specifications of processor 0–processor N, respectively. It is important to note that N is the number of logical CPUs
In general, we think that a CPU can have multicore, plus Intel's Hyper-Threading Technology (HT), can logically divide the number of CPU core out
Number of logical CPUs = number of physical CPUs x CPU cores This specification value x 2 (if HT is supported and turned on)
Note: Linux top view CPU is also the number of logical CPUs
③CPU Number of cores
The number of chipsets that can process data on a CPU, such as the current i5 760, is a dual-core four-thread CPU, while i5 2250 is a quad-core four-thread CPU
In general, the number of physical CPUs x per core should be equal to the number of logical CPUs, if not equal, it means that the server's CPU support Hyper-Threading Technology
㈡ Viewing CPU information
When we are Cat/proc/cpuinfo,
CPUs with the same core ID are Hyper-threading of the same core
CPUs with the same physical ID are the same CPU-encapsulated thread or core
㈢ The following examples illustrate
① View the number of physical CPUs
#cat/proc/cpuinfo |grep "Physical id" |sort |uniq|wc-l
2
② View the number of logical CPUs
#cat/proc/cpuinfo |grep "Processor" |wc-l
24
③ View CPU is a few cores
#cat/proc/cpuinfo |grep "Cores" |uniq
6

"Linux command" Lscpu,, Etc/cpuinfo detailed