Re: [PATCHv4 08/12] Teach the notes lookup code to parse notes trees with various fanout schemes

Hi,

On Fri, 28 Aug 2009, Johan Herland wrote:

On Friday 28 August 2009, Johannes Schindelin wrote:

quoted

And I can easily imagine a repository that has a daily note generated 
by an automatic build, and no other notes.  The date-based fan-out 
just wastes our time here, and even hurts performance.

What about a month-based fanout?

Well, I hoped to convince you that the date-based approach is too rigid.  
You basically cannot adapt the optimal data layout to the available data.

(I like to think of this issue as related to storing deltas: we let Git 
choose relatively freely what to delta against, and do not force a delta 
against the parent commit like others do; I think it is pretty obvious 
that our approach is more powerful.)

So the simplest (yet powerful-enough) way I could imagine is to teach the 
reading part to accept any fan-out (but that fan-out is really only based 
on the object name, nothing else), and to adjust the writing/merging part 
such that it has a maximum bin size (i.e. it starts a new fan-out whenever 
a tree object contains more than a config-specifyable limit).

I was certainly not thinking of something as complicated as Huffman.

Ciao,
Dscho