Day 23: Getting system info under GNU Linux
How many CPU cores you cooking ?
This is one of the many questions that you may end up asking yourself.
Luckily for you, I’m here with all the answers to your questions.
Let’s get into it
CPU - lscpu
Getting the number of CPU cores on your server/PC
lscpu
The neat information that lscpu gives in this case is the number of cores as well as the number of physical sockets.
It means that physically i have only one CPU in one socket on my motherboard (which is true).
The concept of sockets and cores is useful for virtual machines.
See, the number of cores per machine is calculated by:
cores = cores per socket * sockets
In my case: cores = 4 * 1 = 4
CPU - cat /proc/cpuinfo
Unlike lscpu,which summarises all the information.
cpuinfo gives per core information
cat /proc/cpuinfo
I mostly use lscpu due to the fact that it summarizes this information.
Memory - lsmem
lsmem
Total online memory is the main information we’re looking for here!
This means I have 16GB of RAM on this computer (not bad eh!)
Memory - cat /proc/meminfo
cat /proc/meminfo
Here, MemTotal/MemFree/MemAvailable are of interest.
MemTotal - The total available RAM. 16GB that i have physically installed.
MemFree - The RAM that has been allocated and ready to use by the OS.
MemAvailable - The RAM that is not been allocated but ready to be allocated by the OS for use.
PCI - lspci
lspci -m
lspci in machine-readable format.
If you are looking for specific detailed information, use the (-v) flag instead.
Lists all PCI devices/PCI modules of server.
Here, since most of my modules and devices are “ASUSTeK”, we can definitely conclude that I’m using an ASUS motherboard.
My VGA is an nvidia not AMD, and so on.
USB - lsusb
lsusb -t
The tree format gives us bandwidth information which might be useful.
Say we are physically connecting USB storage to our server, and we want to know the bandwidth available to that server.
We can see here, there are buses of :
480Mb/s which is USB 2.0 and
10000Mb/s, which corresponds to USB 3.1.
USB 3.0 would be 4800Mb/s
Storage/LVM - lsblk
lsblk
Shows all block devices information.
Disk partitions and stuff.
