[cap-talk] Price of resource accountability

[Baldur Johannsson]

Curiously enough I have been thinking/experimenting a bit with exactly
this issue.

Three kinds of resources for an protection domain come up in my mind:
  1. memory ( for storing programs both text and state )
  2. cpu-time ( for running an protection domain )
  3. inter protection domain messaging ( to prevent flooding )

Both 1. and 2. are familiar to anyone who as studied KeyKos/Eros/Capros as
they can be achieved by sub-spacebank and sub-meter respectively.
But what about 3.? I havent seen it used/mentioned so far except in
the Agorics Inc.
 paper titled "Digital Silkroad" under the concept of "postage".

So I ask you(plural) this: are these three types of resources inter-fungible?
If that is the case I suggest that an third type of datum primitive (besides
capabilities and normal bit pattern datums) be added to both protected
domain state
and messages: some sort of an quota currency ( basically an big number
say 256 bit one).

Also that the additional behaviour would be added:
The kernel deducts x amount from an protected domains quota currency
amount when said domain is acquiring more memory, creating other
domains and sending messages.
And such operation would fail (with indication) if the domain doesnt
have enough of the quota currency.
The kernel adds x amount to an protected domains quota currency when
it receives an
message from another domain and releases memory.

Quota currency would, as noted above, also be part of every message
giving the option of
a sending domain passing more of it to receiving domain if so desired
by the programmer at
the time.

If anyone is interested in a spec for capForth Actors I clobbered
together then dont hesitate
to ask for it. Though here is a fair warning: it is an documentation
written by an programmer
for himself and assumes familiarity of the Actor Model, capabilities,
Forth and Dual Stack Machines.

I hope this post of mine is pretty free of rambling and need for clarifications.
Cheers
-Baldur