This article is reproduced from: https://www.cnblogs.com/renshengdezheli/p/13427865.html
This article describes the Linux query hype system information, CPU physical number, CPU core number, logical CPU number, memory information query, hard disk information query.
I. Introduction
When we take over one or several servers, we must first have an understanding of the basic configuration of the server, so that we can prescribe the right remedy. For future software deployment, system operation and maintenance will have a multiplier effect.
Two, about the basic configuration of the server
The basic configuration of the query server generally queries the operating system, CPU, memory, and hard disk, which will be explained one by one below.
2.1, basic operating system configuration query
Check the operating system version:
#cat /etc/redhat-release这个命令主要是查看红帽发行的操作系统的版本号
[root@node5 ~]# cat /etc/redhat-release
CentOS Linux release 7.4.1708 (Core)
#cat /etc/issue这个命令适用于大多数linux发行版
[root@node5 ~]# cat /etc/issue
\S
Kernel \r on an \mView the operating system kernel version:
[root@node5 ~]# uname -r
3.10.0-693.el7.x86_64View operating system details:
[root@node5 ~]# uname -a
Linux node5 3.10.0-693.el7.x86_64 #1 SMP Tue Aug 22 21:09:27 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
#从上面这段输出可以看出，该服务器主机名是node5，linux内核版本是3.10.0-693.el7.x86_64，CPU是x86架构
#该命令可以查看更多信息
[root@node5 ~]# more /etc/*release
::::::::::::::
/etc/centos-release
::::::::::::::
CentOS Linux release 7.4.1708 (Core)
::::::::::::::
/etc/os-release
::::::::::::::
NAME="CentOS Linux"
VERSION="7 (Core)"
ID="centos"
ID_LIKE="rhel fedora"
VERSION_ID="7"
PRETTY_NAME="CentOS Linux 7 (Core)"
ANSI_COLOR="0;31"
CPE_NAME="cpe:/o:centos:centos:7"
HOME_URL="https://www.centos.org/"
BUG_REPORT_URL="https://bugs.centos.org/"
CENTOS_MANTISBT_PROJECT="CentOS-7"
CENTOS_MANTISBT_PROJECT_VERSION="7"
REDHAT_SUPPORT_PRODUCT="centos"
REDHAT_SUPPORT_PRODUCT_VERSION="7"
::::::::::::::
/etc/redhat-release
::::::::::::::
CentOS Linux release 7.4.1708 (Core)
::::::::::::::
/etc/system-release
::::::::::::::
CentOS Linux release 7.4.1708 (Core)2.2, CPU basic configuration query
Glossary:
| noun | meaning |
| CPU physical number | The number of CPUs actually inserted on the motherboard |
| Number of CPU cores | The number of chipsets that can process data on a single CPU, such as dual-core, quad-core, etc. (CPU cores) |
| Number of logical CPUs/number of threads | In general, logical CPU = number of physical CPUs × number of each core, if they are not equal, it means that the server's CPU supports hyper-threading technology |
View the physical number of CPUs:
[root@node5 ~]# grep 'physical id' /proc/cpuinfo | sort -u | wc -l
1View the number of CPU cores:
[root@node5 ~]# grep 'core id' /proc/cpuinfo | sort -u | wc -l
4View the number of CPU threads:
#逻辑cpu数：一般情况下，逻辑cpu=物理CPU个数×每颗核数，如果不相等的话，则表示服务器的CPU支持超线程技术（HT：简单来说，它可使处理#器中的1 颗内核如2 颗内核那样在操作系统中发挥作用。这样一来，操作系统可使用的执行资源扩大了一倍，大幅提高了系统的整体性能，此时逻#辑cpu=物理CPU个数×每颗核数x2）
[root@node5 ~]# cat /proc/cpuinfo| grep "processor"|wc -l
4
[root@node5 ~]# grep 'processor' /proc/cpuinfo | sort -u | wc -l
4Check the CPU model:
[root@node5 ~]# cat /proc/cpuinfo | grep name | sort | uniq
model name : Intel(R) Core(TM) i7-8550U CPU @ 1.80GHz
[root@node5 ~]# dmidecode -s processor-version | uniq #使用uniq进行去重
Intel(R) Core(TM) i7-8550U CPU @ 1.80GHzView the detailed information of the CPU:
#CPU有几个核，就会输出几个重复的信息
[root@node5 ~]# cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 142
model name : Intel(R) Core(TM) i7-8550U CPU @ 1.80GHz
stepping : 10
microcode : 0x96
cpu MHz : 2000.921
cache size : 8192 KB
physical id : 0
siblings : 4
core id : 0
cpu cores : 4
apicid : 0
initial apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 22
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss ht syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon nopl xtopology tsc_reliable nonstop_tsc eagerfpu pni pclmulqdq vmx ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm 3dnowprefetch tpr_shadow vnmi ept vpid fsgsbase tsc_adjust bmi1 avx2 smep bmi2 invpcid mpx rdseed adx smap clflushopt xsaveopt xsavec arat
bogomips : 4002.00
clflush size : 64
cache_alignment : 64
address sizes : 43 bits physical, 48 bits virtual
power management:View the detailed information of the CPU:
[root@node5 ~]# lscpu
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
CPU(s): 4
On-line CPU(s) list: 0-3
Thread(s) per core: 1
Core(s) per socket: 4
Socket(s): 1
NUMA node(s): 1
Vendor ID: GenuineIntel
CPU family: 6
Model: 142
Model name: Intel(R) Core(TM) i7-8550U CPU @ 1.80GHz
Stepping: 10
CPU MHz: 2000.921
BogoMIPS: 4002.00
Virtualization: VT-x
Hypervisor vendor: VMware
Virtualization type: full
L1d cache: 32K
L1i cache: 32K
L2 cache: 256K
L3 cache: 8192K
NUMA node0 CPU(s): 0-3
Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss ht syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon nopl xtopology tsc_reliable nonstop_tsc eagerfpu pni pclmulqdq vmx ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm 3dnowprefetch tpr_shadow vnmi ept vpid fsgsbase tsc_adjust bmi1 avx2 smep bmi2 invpcid mpx rdseed adx smap clflushopt xsaveopt xsavec aratSummary of CPU configuration:
Through the above query, we can know that the server is a 4-core CPU with 1 channel, the CPU model is Intel(R) Core(TM) i7-8550U CPU @ 1.80GHz, and the CPU does not have hyperthreading.
2.3. Query of basic memory configuration
Glossary:
| noun | meaning |
| Mem | Overview table of memory usage |
| Swap | Virtual Memory. That is, the data can be stored on the hard disk. When the physical memory is insufficient, part of the hard disk space is used as the SWAP partition (virtualized as memory) to solve the problem of insufficient memory capacity. SWAP means swap. As the name implies, when a process requests the OS to find insufficient memory, the OS will exchange the temporarily unused data in the memory and place it in the SWAP partition. This process is called SWAP OUT. When a process needs these data and the OS finds that there is free physical memory, it will exchange the data in the SWAP partition back into the physical memory. This process is called SWAP IN. Of course, the swap size has an upper limit. Once the swap is used up, the operating system will trigger the OOM-Killer mechanism to kill the process that consumes the most memory to release the memory. |
| shared | Shared memory, the physical memory value shared with ordinary users, is mainly used for inter-process communication |
| buffers | Used to store data to be output to disk (block device) |
| cached | Store the data read from the disk |
| total | Total physical memory, total = used + free |
| used | Used memory |
| free | Free memory |
Query server memory:
[root@node5 ~]# free -m
total used free shared buff/cache available
Mem: 3941 286 3446 19 208 3407
Swap: 2047 0 2047
#注释
#linux的内存管理机制的思想包括（不敢说就是）内存利用率最大化。内核会把剩余的内存申请为cached，而cached不属于free范畴。当系统运#行时间较久，会发现cached很大，对于有频繁文件读写操作的系统，这种现象会更加明显。直观的看，此时free的内存会非常小，但并不代表可##用的内存小，当一个程序需要申请较大的内存时，如果free的内存不够，内核会把部分cached的内存回收，回收的内存再分配给应用程序。所以#对于linux系统，可用于分配的内存不只是free的内存，还包括cached的内存（其实还包括buffers）。
#对于操作系统：
#MemFree=total-used
#MemUsed = MemTotal - MemFree
#对于应用程序：
#MemFree=buffers+cached+freeQuery the memory every 3 seconds:
[root@node5 ~]# free -s 3
total used free shared buff/cache available
Mem: 4036316 361144 3458272 19536 216900 3419776
Swap: 2097148 0 2097148
total used free shared buff/cache available
Mem: 4036316 361144 3458272 19536 216900 3419776
Swap: 2097148 0 2097148
total used free shared buff/cache available
Mem: 4036316 361144 3458272 19536 216900 3419776
Swap: 2097148 0 2097148
2.4, query the basic configuration of the hard disk
Query the overall disk usage:
[root@node5 ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 17G 4.1G 13G 24% /
devtmpfs 2.0G 0 2.0G 0% /dev
tmpfs 2.0G 8.0K 2.0G 1% /dev/shm
tmpfs 2.0G 8.7M 2.0G 1% /run
tmpfs 2.0G 0 2.0G 0% /sys/fs/cgroup
/dev/sda1 1014M 125M 890M 13% /boot
tmpfs 395M 0 395M 0% /run/user/0
#命令拓展
#df -a 显示全部的文件系统的使用情况
#df -i显示inode信息
#df -k 已字节数显示区块占用情况
#df -T 显示文件系统的类型Query the disk occupancy of a directory:
#命令拓展
#du -s 指定目录大小汇总
#du -h带计量单位
#du -a 含文件
#du --max-depth=1 子目录深度
#du -c 列出明细的同时，增加汇总值
[root@node5 ~]# du -sh /home/
1.7G /home/
[root@node5 ~]# du -ach --max-depth=2 /home/
4.0K /home/www/.bash_logout
4.0K /home/www/.bash_profile
4.0K /home/www/.bashrc
4.0K /home/www/web
16K /home/www
4.0K /home/nginx/.bash_logout
4.0K /home/nginx/.bash_profile
4.0K /home/nginx/.bashrc
12K /home/nginx
4.0K /home/esnode/.bash_logout
4.0K /home/esnode/.bash_profile
4.0K /home/esnode/.bashrc
4.0K /home/esnode/.oracle_jre_usage
4.3M /home/esnode/elasticsearch-analysis-ik-6.2.2.zip
80M /home/esnode/kibana-6.2.2-linux-x86_64.tar.gz
300M /home/esnode/x-pack-6.2.2.zip
28M /home/esnode/elasticsearch-6.2.2.tar.gz
4.0K /home/esnode/.bash_history
294M /home/esnode/elasticsearch-6.2.2
4.0K /home/esnode/.ssh
4.0K /home/esnode/x-pack生成的秘钥.txt
1014M /home/esnode/kibana-6.2.2-linux-x86_64
8.0K /home/esnode/.viminfo
1.7G /home/esnode
1.7G /home/
1.7G totalView the directory structure:
#tree命令默认没有安装，需要手动安装一下
[root@node5 ~]# yum -y install tree
#-L指定目录深度
[root@node5 ~]# tree -L 2 /home/
/home/
├── esnode
│ ├── elasticsearch-6.2.2
│ ├── elasticsearch-6.2.2.tar.gz
│ ├── elasticsearch-analysis-ik-6.2.2.zip
│ ├── kibana-6.2.2-linux-x86_64
│ ├── kibana-6.2.2-linux-x86_64.tar.gz
│ ├── x-pack-6.2.2.zip
│ └── x-pack\347\224\237\346\210\220\347\232\204\347\247\230\351\222\245.txt
├── nginx
└── www
└── web
6 directories, 5 filesDisplay all available block device information in a tree format:
[root@node5 ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 20G 0 disk
├─sda1 8:1 0 1G 0 part /boot
└─sda2 8:2 0 19G 0 part
├─centos-root 253:0 0 17G 0 lvm /
└─centos-swap 253:1 0 2G 0 lvm [SWAP]
sdb 8:16 0 1G 0 disk
└─sdb1 8:17 0 200M 0 part
sr0 11:0 1 1024M 0 rom
#注释
#NAME —— 设备的名称
#MAJ:MIN —— Linux 操作系统中的每个设备都以一个文件表示，对块（磁盘）设备来说，这里用主次设备编号来描述设备。
#RM —— 可移动设备。如果这是一个可移动设备将显示 1，否则显示 0。
#TYPE —— 设备的类型
#MOUNTPOINT —— 设备挂载的位置
#RO —— 对于只读文件系统，这里会显示 1，否则显示 0。
#SIZE —— 设备的容量List all available devices, universally unique identifier (UUID), file system type, and volume label:
[root@node5 ~]# blkid
/dev/sda1: UUID="6503b4ad-2975-4152-a824-feb7bea1b622" TYPE="xfs"
/dev/sda2: UUID="nqZ4uJ-ksnN-KzYS-N42b-00m3-Ohc2-BJXunP" TYPE="LVM2_member"
/dev/sdb1: UUID="94396e17-4821-4957-aa76-d41f33958ff5" TYPE="xfs"
/dev/mapper/centos-root: UUID="c1d38b37-821d-48e7-8727-3937ccc657a4" TYPE="xfs"
/dev/mapper/centos-swap: UUID="c2fcaf11-42d8-4e4c-bf9e-6464f0777198" TYPE="swap"