maaku wrote:rapso,
I'm sorry I don't have the time to engage in a full discussion on this
but your try is pretty good.
* Linux can be streamlined to an embedded profile, but at the cost of many man hours initially and continually in maintenance. Easy for a corporation to do, not so much for a loose-nit homebrew community.
... but that was not the point.
* The existing kernels are all desktop/server derived variants of Linux. There is not, to my knowledge, any true real-time Linux kernel for the PS3/Cell. Real-time linux is always highly-coupled with the architecture that it is designed for, and developing such a kernel for PS3/Cell will take a non-trivial amount of time and resources to do properly. It's not just a matter of hitting some checkboxes and compiling.
that was just an example and also not the point.
* The ps3sdk has very small, but very specific needs that do not match up very closely with Linux (even with the patches Sony and those on this forum have made).
yeah, I think that's why its written from scratch, rather than porting yet again another kernel.
* Don't fall into the "Linux will be easier because it's Linux" fallacy. Linux is around ~3 million lines of code. MINIX is just 4000 lines of kernel code. L4 is of similar size, and already ported to 64-bit PowerPC. That's three orders of magnitude difference (yes, I know we are comparing micro- to macro-kernels, but for reasons of software engineering complexity it is relevant). What's more, these kernels already have reliable implementations of feature sets needed for real-time embedded programming and are simple enough to not require the extensive tweaking in the port that Linux RTOS options do.
that was just my sample for you, so you dont fall into "[place here any existing os] will be easier, because it's already there".
Most people don't know, or underestimate even if they do the amount of work that must go into creating and maintaining a custom linux kernel for a real-time application. It is my professional opinion that the ps3sdk could be finished faster, and with better satisfaction by adopting an existing, smaller, non-Linux solution.
and from what i've seen, mc is pretty good in ramping up his own micro kernels.
EDIT: But perhaps we should agree to disagree, if you're still not convinced.
yeah, and probably mc coded as many lines as we wrote, but on his kernel ;)