RE: More History comments

> This could prove to be a 
> scalability issue; if every minor change in the archive 
> results in a lot of things having a different situation, then 
> the history system will rapidly become an enormous corpus of 
> data.  Maybe that's OK.  My point is that as far as I'm aware 
> this vital issue hasn't been looked at even vaguely in the 
> original or current work of the History system.

The original History System work did indeed consider this, as well as some of the issues raised here regarding hash-based naming and differences among situations.
For example see [1].  I am encouraged, though, by the vigor of review that we are seeing in this discussion, which complements that prior work.

[1] History Requirements
    http://lists.w3.org/Archives/Public/www-rdf-dspace/2003May/0099.html

> -----Original Message-----
> From: Tansley, Robert [mailto:robert.tansley@hp.com] 
> Sent: Thursday, May 22, 2003 3:54 PM
> To: Kevin Smathers; Tansley, Robert
> Cc: (www-rdf-dspace@w3.org)
> Subject: RE: More History comments
> 
> 
> 
> > The question is why you decided to use BND1:1 rather than 
> BND1:2.  If
> > the choice of BND1:1 was required because the resource at 
> > that node is 
> > identified by a content based identifier, then information 
> > has been lost 
> > about the distinct nature of the two instances.  The graph 
> > looks wrong; 
> > the second chain is logically independent of the first, yet you've 
> > combined the nodes early in the chain, dividing them only where the 
> > content has changed.  I think you instead should consider the 
> > instance 
> > chain to be independent of the content (see attachment.)
> 
> Hi Kevin,
> 
> Your attachment shows the logical conclusion of following the 
> logic I was trying to describe; that basically, if you change 
> anything in the archive, since things in the archive are 
> related changing one thing changes the situation that 
> everything related to that changes.  This could prove to be a 
> scalability issue; if every minor change in the archive 
> results in a lot of things having a different situation, then 
> the history system will rapidly become an enormous corpus of 
> data.  Maybe that's OK.  My point is that as far as I'm aware 
> this vital issue hasn't been looked at even vaguely in the 
> original or current work of the History system.
> 
>  Robert Tansley / Hewlett-Packard Laboratories / (+1) 617 551 7624
>