Hi, On Sat, Jan 17, 2009 at 01:38:11AM +0000, Zheng Da wrote: > On Thu, Jan 15, 2009 at 11:03 AM, <olafbuddenha...@gmx.net> wrote:
> > Indeed, while the primary goal is running subhurd as normal user, it > > is evidently a desirable variation to have a completely isolated > > subhurd. [...] > I don't really accept this option. I see subhurd as a substitute of > the virtual machine where can only run Hurd, at least, it's what I > hope subhurd should be. This is not entirely true: At least in theory, it should be possible to run *any* Mach-based system... Admittedly, there are few others left ;-) > So if I runs two subhurd, what I wants is an isolated environment to > do some experiments, but somehow the program in one subhurd can crash > the other subhurd. Isn't it very strange? That really depends on the situation. Total isolation is not always desirable. The flexibility is indeed the major advantage of Hurd-based virtualization, as I pointed out in http://tri-ceps.blogspot.com/2007/10/advanced-lightweight-virtualization.html > Since I think subhurd as a virtual machine, I hope it can give more > control of resource usage to the user. For example, limit its memory > usage (It's the only example I can think of now:-). Unfortunately this is not possible with the current Mach-based Hurd implementation. The impossibility of tracking memory usage in the existing implementation was in fact the major motivation (or at least one of the major motivations) for the Hurd/L4 port; and it's also the focus of Neal's current research work. I'm not saying that it's impossible to add such abilities -- but it will require very fundamental changes both to Mach and to the Hurd... -antrik-
