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[ Welcome! ]

A quick Introduction...

Welcome to the Citadel Homepage, here you can find all kinds of Downloads and Information related to the Citadel Project.

Alrighty, so just what is Citadel?

Citadel is a Microkernel in developement, designed to be fast, reliable, heavily customizable and compatible with today and tommorow's 32bit x86-compatible Processors.

Citadel is being designed from the bottom up to give you the choice in how you want your system to run, and actually being able to make and execute that choice without having to spend weeks reading Manuals or Tutorials.

Microkernel? Reliability? Customizability?

All Operating Systems have a heart and that heart, dear reader, is called a Kernel. Up until fairly recently, Desktop OSes have utilized Monolithic kernels (or variants) which house as many drivers as possible within the Kernel's codebase, or allow you to 'insert' Modules which automatically link into the Kernel during insertion. While these Kernels have been successful, they often crash (In Windows case) due to badly programmed Drivers. Why? Well, since the drivers are either directly in the Kernel's codebase, or inserted into the Kernel's code on-startup, mistakes that would have once just been annoying become fatal, since a Memory-related bug could end up overwriting important chunks of data or even the Operating System itself causing a painful system crash.

A Microkernel is designed to provide only the bare essentials that are required to get external applications functioning on your system, within protected space. This includes Drivers of any kind. Since the Kernel only holds the bare minimum, it should theoretically be easier to maintain and more reliable due to the fact that there will ultimately be less code to debug and improve over time. And since Drivers themselves are considered ordinary Applications so if they are buggy and crash, the Kernel will continue to run! Yay, No crashes due to crappy driver programming!

Customizability is granted thanks to the fact that everything that isn't 100% neccessary is seperated from the Kernel and executed within Userspace. There are no forced design decisions placed on you, if you want to run a different GUI than the one to be included with Citadel, go for it. Almost everything can be changed without serious technical knowledge. Drivers, Command lines, whatever - can all be installed just like an ordinary program. And for those people with technical knowhow: the sourcecode to Citadel is 100% Opensource, if you dont quite like the response time of your Applications running, or maybe the way Memory is being handled, feel free to download the sourcecode to the Kernel itself and make it work how you wish, just do me a favor and email the modified sourcebase back to me for cataloguing. Someone else may find your modifications useful.

Ok, Im almost convinced. You mentioned Speed?

Technically, a Microkernel will be slower than a identically featured Monolithic kernel. But then, that Monolithic Kernel would only have Memory Management, Process scheduling and Interrupt Handling. The theoretical speed gains from a Microkernel again, comes down to the fact that only essential components are included in the Kernel code, resulting in a tight, closely integrated system core. If you need extra speed and dont need Networking, Sound or whatever else - you can just terminate the Servers(Drivers) providing those features, giving you a few more clock cycles to spend elsewhere. But hey, like I said, the speed gain is theoretical ;)

[ Want extra information? ]

Several websites contain information about the different types of Kernels commonly used in today's operating systems. If you are interested in the specifics, Wikipedia has some very good articles concerning them. Just do a search on Monolithic / Micro / Modular Kernels and you are sure to find something!. Google is also useful.

If you are interested in the deeper aspects of Microkernel (and Operating System) developement, there are no better places than the Mega-Tokyo OS Developement Boards and the Mega-Tokyo OS-FAQ

Failing either of these, you could always gawk over the Citadel design notes and sourcebase.

Anywho, that's enough out of me!
~Zeii.

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