Re: Reverse-delta storage

Jim Blandy wrote:

> Branko =?ISO-8859-2?Q?=C8ibej?= <brane@xbc.nu> writes:
>
>> I'll think about this a bit. Surely it should be possible to optimise a
>> composed vdelta?
>
>
> Surely. We wait with bated breath. :)

Working on that. (I'm trying to find out if deltas form a Hilbert space.
Might get some interesting results if they do. Of course, first I had to
dust off a few textbooks to help me remember what a Hilbert space is. :-( )

>> This gives me an idea: When we're retreiving a revision that's more than
>> one step away from the head, we could replace its representation with a
>> delta to the current fulltext. It's even possible the combined delta is
>> smaller than the original, and there's no reason we can't have several
>> references to the same (fulltext) node. (post-1.0: write a repository
>> compaction tool that minimizes the number of delta compositions needed
>> to retreive a node, and finds the smallest possible deltas for the
>> representation).
>
>
> Finding the smallest set of trees that reconstructs a given series of
> revisions sounds like an interesting problem.

"Interesting" is right. That's why I'm not working on this right now. :-)

-- 
Brane �ibej
    home:   <brane_at_xbc.nu>             http://www.xbc.nu/brane/
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