Thursday, November 14, 2019

Fedora 31 : Can be better? part 001.

I started using Fedora distribution several years ago after I tried several distros (Suse, RedHat 6, Debian, Gentoo and many more).
I was pleased with the test and speed.
I must admit that from the first used version 9 (Sulfur) and until now it is very changed and unknown for many users
That's why I decided to present in this series of mini-tutorials called Can be better? various lesser-known aspects that underlie it and its more precise use.
I will not abide by a predetermined order in the use of Fedora distribution.
I will only point to useful information for any Fedora user.

Let's start the first part of this tutorial named Can be better? part 001. with a brief introduction to the Wikipedia page and the official one.
An interesting aspect of Fedora configuration is the file sysctl.conf.
You can read the manual page with this command:
man 8 sysctl
Part of this file should contain these lines:
vm.overcommit_memory=2
vm.overcommit_ratio=100
kernel.exec-shield=1
This parameter named vm.overcommit_memory can be set this way:
0: heuristic overcommit (this is the default)
1: always overcommit, never check
2: always check, never overcommit
For this parameter named vm.overcommit_ratio any value to anything less than 100 is almost always incorrect.
The last parameter named kernel.exec-shield fix NX protection also called Data Execution Prevention (DEP), to prevent buffer stacks from taking down your machine.
You can check this with:
[root@desk mythcat]# grep nx /proc/cpuinfo