# total number of cores = number of physical CPUs X number of cores per physical CPU
# Total Logical CPUs = number of physical CPUs x number of cores per physical CPU X number of hyper-threads
# View the number of physical CPUs
cat/proc/cpuinfo| grep "Physical ID" | Sort| uniq| Wc-l
# See the number of cores in each physical CPU (that is, the number of nuclei)
cat/proc/cpuinfo| grep "CPU Cores" | Uniq
# View the number of logical CPUs
cat/proc/cpuinfo| grep "Processor" | Wc-l
# View CPU information (model)
cat/proc/cpuinfo | grep name | cut-f2-d: | uniq-c
dstat mpstat iostat vmstat netstat nfsstat ifstat
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
I should be 2 CPUs, each CPU has 6 cores, should be Intel's U, support Hyper-threading, so display 24
Linux Viewing System Tools