[cap-talk] How desirable / feasible is a persistent OCAP language?

Sandro Magi naasking at higherlogics.com
Wed Jul 23 09:23:12 CDT 2008

James A. Donald wrote:
> Assume the state of an object on one machine has
> dependencies on the state of another object on another
> machine - that for the system to work correctly, one
> machine's state embodies assumptions about another
> machine's state.  As a result of software changes,
> hardware changes, reorganizations of information driven
> by storage limits, unforeseen bugs that have to be
> corrected, and so forth some of these assumptions become
> invalid.  It is difficult to remedy this except by
> recreating all the objects from scratch at the same time
> or in proper sequence, but if they are permanent
> objects, they probably embody, or have come to embody, a
> lot of information that is costly to recreate.

So in summary, the crux of the matter is that making assumptions about 
other machines is harmful in a distributed system, not that 
durable/persistent objects in and of themselves are harmful. I think I 
agree with that phrasing, but not the stronger assertion that durable 
objects themselves are to be avoided at all costs.


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