Distribution semantics: database consistency -- transactions

Mike Prince mprince@crl.com
Wed, 9 Nov 1994 13:43:20 -0800 (PST)

On Wed, 9 Nov 1994, Raul Deluth Miller wrote:

> I've been thinking about "resource quantification" mechanisms, and
> while I'm not quite ready to lay down my proposal, I should mention
> that available network bandwidth could be included in such
> quantification (e.g. to superceed some timeout when it's expected that
> a calculation will take rather long).

Absolutely.  We can imagine the threading of execution between tool boxes 
as virtual links.  Here are some of the data we might have about those links;
	Average comunications demands (bytes/second)
		May be used to allocate "channels" for video information, 
		as in you have a 100Mbs LAN, each video channel is 
		10Mbs, so only allow 10 links to use the LAN.
	Max acceptable latency (nano/pico seconds resolution?)
		For use in real-time systems
	Prioritization of Links
		If a tool box relies on 30 links, 5 of those should 
 		be close for performance reasons, and the rest of those
		are rarely used, have their priority numbers reflect that.
	Burst communications demands
		A link is rarely used, but once in a while it gets busy.
	Min acceptable data rate
		Don't try to send interactive video through your dial-up

These are just some ideas thrown out.  What I'd like to do is have each 
tool box include as one if its data stacks an ordered list of its 
"links", including performance requirements like the above, and maybe 
augmented by the system itself with a profile of actual resource usage.

During re-allocations of resources this data could be used.

So whaddya think?