On 6/27/07, Alan Grimes <agrimes@speakeasy.net> wrote:
The problem with L4 on the other hand is that it doesn't have an
operating system wrapped around it in order to make it usable... I have
a number of earth-shaking projects ...
Can you share some?
Got a counterexample of an installable and usable L4 development system?
I think L4Env or Kenge + Iguana can do some work, through they are not mature yet.
IMHO (plese excuse me if it is not proper), we must have an unified development environment to make L4 more attractive and get more attentions.
I think L4Env is easier to understand for new comers, however most parts of the public release only support V2/X0 API, and there is never complete and up-to-date documentation or roadmap. The organization of source tree is confusing without a clear architecture. Various components and changes just emerge from time to time.
I believe if L4Env can support X2 API and is reorganized / redesigned to reflect an explicit system architecture with confusing legacy code discarded, it will be much more popular and can greatly boost the development of L4.
To me, Iguana is not good to understand, especially that there are much ambiguity in the specification. It is more like an academic report than a technical manual, and it seems that some concepts are still in development and so hard to correspond to source code.
Moreover, Iguana is just a new single-address space "mono-kernel" in user level, it provides only a basic set of services and is far from enough to construct an usable system. We can not always rely on a virtualized Linux which eliminates the advantage of a u-kernel. I know that the new Iguana API is under development, however, again there is not a clear roadmap released.
It seems that both OS Group in TUD and ERTOS in NICTA focus more on their new L4 API. IMHO, seL4 and L4.sec may be great work in academic sense (and may relate to commercial considerations in future), but at present a strong development environment for existing kernels and APIs may be more important to expanding the influence of L4, and better meet the appetite of most open-source programmers (of course, these may not be what you concern).
As for Minix3, it grows fast since last year due to good organization and open strategy that attracts open-source programmers. And I think maybe one day, it will become more influential than L4 if things progress as now. An successful system may not be the one do best in specific aspects, but should be one that works.
Regards,
Wei Shen