Messages in this thread | | | Date | Wed, 1 Oct 1997 21:40:35 -0300 (EST) | From | Fabio Olive Leite <> | Subject | Re: Process Migration on Linux - Impossible? |
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Hi there,
> I don't think process migration is such a bad idea, I just think that the > costs don't out weigh the benefits. I'm not saying that it can't be done, > I'm saying that it shouldn't be done, especially not at the expense of > normal OS performance, reliability, and maintainablity (adding code to > the kernel is mutually exclusive with all of those in almost all cases).
I'm going to put as little code on the kernel as possible. I won't transform Linux into a migration-dependent OS. The kernel will help on the migration, but a Linux system without the "migration daemon" won't migrate anything, it will just work as any other independent system. A Linux system with the migration daemon (migd for short), but without the policy daemon won't migrate processes at will, unless someone tells migd that it should migrate something.
It's a very modular thing, each part doing only it's own job, and I'd like to get as little overhead as possible on the kernel, so that other things don't get too slow.
> So here's a question: if it worked and was useful, why has that facility > not made it into any sucessful commercial or free operating systems? Was > it ahead of its time or is there some inherent reason?
How would you go about migrating a Windows95 process, when it's so close to the hardware? What use is there for migration on a net of Word loaders?
People that use Windows95 just don't need migration. People who run some Unix sometimes do, as usually they do some number crunching and other CPU bound ativities that could take advantage of it.
I just received a mail telling that AIX for PS/2 had migration some years ago.
> The point is that yes, you can do it. But that is an academic point, > not anything that is actually useful. Not in my experience. I'm happy > to be proven wrong, but I'm unhappy with letting people go down a > proven rathole.
That's why I'm doing it, I'm graduating in Computer Science. I started this thread to get some comments and suggestions about it, not to ask people if they wanted migration on _their_ Linuxes. If you don't want, don't use it, period. Heck, I don't even dream about getting it on mainstream Linux!
Hope this "you can't do this to Linux" stuff ends. If people get interested on my work, I'll distribute patches on my pages, one day.
[] Fabio ( Fabio Olive Leite leitinho@akira.ucpel.tche.br ) ( Computing Science Student http://akira.ucpel.tche.br/~leitinho/ ) ( ) ( LOADLIN.EXE: The best Windows95 application. [Debian GNU/Linux] )
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