[glue-wg] Publishing annotations

[Burke, S (Stephen)]

Paul Millar [mailto:paul.millar at desy.de] said:
> > In principle that could be changed in the 
> > kind of way you describe - but you'd then have a special-purpose
> > solution for this specific case rather than something which 
> would work
> > in general.
> 
> Well, I don't think this is so specialised.  In general, a 
> UserDomain might 
> want to mark any Service as "Sane" (i.e., has been tested).  
> This isn't limited to any specific type of service.

Indeed, but it doesn't help with other kinds of things - in particular
with downtime, which is unusable by EGEE as it's currently represented.
Perhaps we just say that we don't care, but it still seems odd to me to
introduce something in a way which can't work for one of the major
grids.

> Yes, I meant to ask out of idle curiosity: why is this?  If 
> an SE unavailable, 
> (drops out of info-system) it's almost necessarily 
> unavailable.  Why does FTS care about it?

Because it does the scheduling of transfers in advance of when it
actually performs them. Actually you could have the same with the WMS,
in theory it could schedule jobs and then hold them if the CE wasn't
available. The difference is that jobs can often run on many CEs so it's
better to pick one which is working, whereas file transfers always
involve specific SEs so if they're down you have to wait.

> Well OK, but the problem is (to my mind) that that process is 
> broken anyway:  
> use the info system to discover how to ask the info system.

I had a discussion on this with Maarten recently, and he also favoured
direct configuration vs discovery. My point would be that in a large
grid you may have hundreds of top-level BDIIs and hand-configuration
becomes very hard - although you obviously have to configure at least
one to get you started. You can compare with R-GMA, where the client is
configured with the address of the local MON box but everything else is
automatic, although the discovery is internal rather than via the Glue
schema.

Stephen