GNU/Linux

Introduction

GNU/Linux est un système d'exploitation dont l'objectif est de rendre son utilisateur complètement maître de son informatique. Pour ce faire, chacun de ses composants doit respecter les quatre libertés essentielles du logiciel libre :

Howto

Rotate photos
How to rotate photos with an incorrect EXIF Orientation tag.
Set time
Set time of a computer's clock.

Lemote Yeeloong

Lemote est un constructeur chinois d'ordinateurs à processeur Loongson. La série Yeeloong comprend les ordinateurs portables proposés par Lemote.

Mon but

J'utilisais gNewSense comme système d'exploitation principal sur mon Yeeloong, ce système étant basé sur le port MIPSEL de debian stable. Dans l'ensemble, j'en étais plutôt satisfait, mais je souhaitais avoir une meilleure réactivité ainsi qu'un meilleur contrôle des logiciels, démons et services qui étaient sur mon ordinateur. Pour ces raisons, j'ai écrit le document GLLFSC (GNU/Linux-libre from source code). Et GLLFSC est désormais mon système d'exploitation principal.

Quelques pages qui m'intéressent en ce moment :

musl
Une bibliothèque C pour le noyau Linux, minimaliste et adaptée à la liaison statique aux exécutables.
La loi de Wirth
Les programmes ralentissent plus vite que le matériel accélère. Exemples : l'exécutable pour GNU/Linux de Firefox 1.0.8 (2006) pesait 7,9 Mo (en tar.gz), pour la version 33.1.1 (2014), il pèse 41 Mo (en tar.bz2 !). Comparaison du matériel minimal nécessaire pour Microsoft Windows (x86, source : Wikipedia) :
Version de Windows Processeur Memoire vive Disque dur
Windows 95 25 MHz 4 Mo 50 Mo
Windows 98 66 MHz 16 Mo 200 Mo
Windows 2000 133 MHz 32 Mo 650 Mo
Windows XP (2001) 233 MHz 64 Mo 1500 Mo
Windows Vista (2007) 800 MHz 512 Mo 15 Go
Windows 7 (2009) 1 GHz 1 Go 16 Go
Windows 8 (2012) 1 GHz 1 Go 16 Go

Today's computers have gotten very fast. Moore's Law states the the number of transistors that can be built into a microchip will double every two years. Theoretically, this means that (in general) the speed of a computer doubles every two years. This law has been proven to hold true for a long time now. Computer processors get faster and faster as time progresses, and also use less power.

So, a computer from two years ago should be twice as slow as a new computer today, correct? That would be true, if computers were only hardware, but computers also need software to perform any kind of useful task. Wirth's Law states that computer software is becoming slower faster than computer hardware is becoming faster.

The modern software developer has gotten quite lazy. When computer programming was beginning, programmers had to be careful not to use too many resources, and to make sure their programs ran as efficiently as possible. Many programs were written in Assembly in that day. Then computers got faster, and faster and faster, and now today, programmers write code in C#, or Java, which gets compiled to byte-code (not machine code) and interpreted by a virtual machine, and uses garbage collection, because today's programmers are too lazy to even manage memory properly, I can't think of a better way to waste resources. Nowadays, everybody is worried about "going green" and conserving our planet's resources, but in the meantime we are wasting all of our computer machine's man-made resources.

How do programmers get away with writing such bad code, you ask? They don't care, and many of them believe that computers are so fast now that no one will notice. Unfortunately, nobody is noticing, but the only reason is because nobody knows what good software looks like anymore. Computers used to run on 64 megabytes of RAM with 1 gigabyte hard drives, now we have 2 terabyte hard drives and 4 gigabytes of ram, and we still use all of it. We don't do new things, we watch videos, write documents, browse the web, so why do we need all that RAM and hard drive space?

Because application programming has gone to hell.

http://betteros.org/

Autres documents intéressants

Le projet GNU HURD est un noyau multi-serveur qui permet une gestion complètement modulaire des pilotes contrairement à un noyau monolithique tel que le noyau Linux.

GNU/HURD à partir des sources
Construire son système GNU/HURD à partir des sources (document en chinois).