Re: [9fans] Multi-dimensional filesystem

[tlaronde@polynum.com]

On Wed, Aug 15, 2012 at 07:04:28PM +0300, Eugene Gorodinsky wrote:
> I'm sure I must not understand the problem fully and am confused because of
> that, but how is this idea of multidimensionality different from a
> relational filesystem approach such as befs (
> http://www.nobius.org/~dbg/practical-file-system-design.pdf)?

One can obviously mimick what I have described with a database, fields,
the relationships being built by indexing.

The hierarchical (but with multiple parents as well as multiple
children) is a representation of the indexing in this case.

So the BeFS could---from a cursory look about the combination of
database, indexing and hierachy representation---offer a solution,
except that the multiple parents, is not there (this could be, as well
as with other systems, be done with .+ and .- presentation).

The main differences from what I have in mind are:

1) There is no general relational database concept: the relationships of
the "records" (files, that can have both a text content [the definition
in my example] and be a directory node) is exclusively isomorphic to
coordinates: (i, j, k, ...).

2) There is no constraint in the size of the "fields": the dimension can
grow with time (no given dimensions coordinates being, by convention,
equal to 0 to reach the actual dimension) ; there is no limit (except
implementation one) for the size of an enumeration.

3) The hierarchy is the user interface, to view and to add the data: a
new file (record) is added by placing it in the hierarchy; while in a
relational database, the indexing is deduced from the actual records;
here, so to say, the data is entered through the indexing.

4) And the problem was also thought through 9P: is there something in 9P
that would prevent, at least theoritically, such a view of data to be
presented? With the convention of ".+" and ".-", my answer is no: 9P has
no hardcoded knowledge of ".." if I'm not mistaken.

--
        Thierry Laronde <tlaronde +AT+ polynum +dot+ com>
                      http://www.kergis.com/
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