[Swift-devel] Re: scheduling

[Mihael Hategan]

On Wed, 2010-03-31 at 03:43 +0530, Vipul Kumar Singh wrote:
> Hi,
> 
> Going through the code i realized that we could add to the
> checkConstraints() which returns the desired sites to the
> getNextResource()...

You're close to what I think should be done.

My opinion is that availability of files should bias the site scores
instead of imposing hard constraints. There would be a parameter that
would control the strength of that bias.

>  We can add data dependencies as task constraints, the constraints
> checker then checks the availability of data on sites based on
> catalog, as you suggested. So the logical step would be to have the
> support for RLS catalog in swift so it can be used to make scheduling
> decisions.
> 
> But I am having trouble figuring out how to get the mappers and
> catalog concept work complementary to each other i.e. what would be
> first steps towards having a catalog of data in swift..

Right. Swift would need some form of data catalog. Perhaps a simple
in-memory catalog would be a good first start. And before that there
would be a need for an API specification to which various
implementations could be plugged (e.g. in-memory, database, RLS).

Also, I would say ignore mappers for now. That is unless Mike has a good
reason for doing otherwise that I'm not aware of.

Mihael