[EROS-Arch] Package handling...

[Joerg Bornschein]

On Wed, Mar 28, 2001 at 11:00:02AM -0500, Jonathan S. Shapiro wrote:

> > Anyway, at some point after having explicit linked new constructors to my
> > shiny new component, i would like to delete the old ones.
> > 
> > But i cant do this -- my packet manager cant be sure if some user (currently
> > not logged in) is using this constructors product. How long should it wait?
> > A week? Two weeks? A month?
> 
> Yes. There is a definite GC problem here, but here are two options:
> 
> 1. Reference counting. We can arrange things so that the constructor
> also destroys, and therefore knows how many objects are outstanding.
> 
> 2. Explicit deletion. Deleting the constructor does not need to cause
> instances to die. They run as long as they run.

I like this one -- but:

 somebody's owning the spacebank where this products code segment
 resides. If you like to keep your products running even if the packet
 manager deletes the space bank, each product must  be carriing around
 his own copy, musn't it? Hmmmm.....

I was thinking about a solution using "Sub-Softwarebanks" this way 
 -- don't know if it's possible:

Lets say each user gets it's own "softwarebank". It is empty, but
inherits all the software from a parent bank -- e.g. systemwide 
applications.

Each individual constructor uses reference counting.

If the application administrator wishes to delete a factory X from 
the systemwide softwarebanki, all affected child banks are informed.
It's now up to them: if they wish to keep the product active, they 
must make a copy and provide the memory space on their own.

I think at least from the view of accountability this is exactly
the desired effect.

Software is a global resource -- but if its taken away, it up to the
individual user/subsystem to keep their own copy.

But it seems the implementations gets a little complex :(


   joerg


-- 
 The known is finite; the unknown infinite.    Intellectually we stand on 
  an islet in the midst of an illimitable ocean of inexplicability. Our
  business in every generation is to reclaim a little more land..
 						    	     --T.H. Huxley