A 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
Two View 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
Three examples below 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
Free-m view memory displays in M size
Cat/proc/meminfo
Top
Df-l Hard Drive condition
This article is from the cloud blog, so be sure to keep this source http://weimouren.blog.51cto.com/7299347/1784675
Y query hard disk memory CPU