Op 25-08-09 21:08, Peter Zijlstra schreef: > On Tue, 2009-08-25 at 14:03 -0400, Christoph Lameter wrote: >> On Tue, 25 Aug 2009, Mike Galbraith wrote: >> >>> I asked the questions I did out of pure curiosity, and that curiosity >>> has been satisfied. It's not that I find it useless or whatnot (or that >>> my opinion matters to anyone but me;). I personally find the concept of >>> injecting an RTOS into a general purpose OS with no isolation to be >>> alien. Intriguing, but very very alien. >> Well lets work on the isolation piece then. We could run a regular process >> on the RT cpu and switch back when OS services are needed? > > Christoph, stop being silly, this offline scheduler thing won't happen, > full stop. > > Its not a maintainable solution, it doesn't integrate with existing > kernel infrastructure, and its plain ugly. > > If you want something work within Linux, don't build kernels in kernels > or other such ugly hacks. Hello, For the one interested in such approach, you can have a look at an now unmaintained project that we developed, ARTiS: http://www2.lifl.fr/west/artis/ It allows several RT tasks to share a "RT" cpu, and if a task tries to "cheat" by calling a kernel function which disables the preemption or the interrupts, it is temporally migrated to another CPU. This is a working approach, with some good low latency results which can be seen in the papers on the website. See you, Eric -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html