[glue-wg] Fwd: Re: New attribute for GLUE 2.1: StorageShare.ViewID

[Paul Millar]

Hi Maria,

On 26/09/14 14:27, Maria Alandes Pradillo wrote:
 > As you say, Physical shares do not publish the Tag attribute,
> so it's easy to know which ones they are.

It doesn't say that in the GLUE 2.0.  It says "An identifier defined by 
a User Domain which identifies a Share with a specific set of properties."

There's nothing written *anywhere* that says only shares without a Tag 
should be used for accounting.

Also, introducing such a rule could break the existing info-providers: 
what about DPM and StoRM?

The point is: yes, I can publish something in dCache info-provider that 
allows a client to get the right answer, but either the client needs to 
know some dCache-special thing, or the solution is fragile and will 
break in the future.

What I want (and what you said you wanted) was all storage systems to be 
handled in the same way.

> That document is for GLUE 1.3. We don't have something similar for
> GLUE 2.0.

True, we hoped it wouldn't be necessary to have a special document for 
GLUE 2.0 as GLUE 2.0 should handle this use-case without profiling.

> And I can tell you WLCG is not interested in getting
> installed capacities correctly published in the BDII. They have given
> up and they have the REBUS interface instead.

Yes, I guess they gave up forcing everyone to use it because the 
initiative failed --- although nobody in WLCG management has made this 
explicit.

What I'm saying is that not everyone has given up: some people still 
want to get the numbers this way.

If we can fix the accounting then it becomes possible.

As you say, the current REBUS accounting is broken: the numbers don't 
match up.  Let's try to fix it.

> I wouldn't introduce this change in the schema only because one site
> has asked for it. Moreover, and after your answer to Stephan (which
> by the way it's a bit confusing) there are ways for that site to
> calculate the installed capacity using the current attributes.

The point is that one can always publish "something" and "somehow get it 
to work".  This is how we published SRM information in GLUE 1.3: naming 
conventions and duplicating information.

With GLUE 2.0, we tried to fix that: to get rid of fragile work-arounds 
like that.  The result is much better but there are still problems.  We 
should try to fix those problems.

Cheers,

Paul.