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Hi Oxana,

> 1. Mailing lists are typically opened for posting only by the members,
> to protect it from SPAM. So please *join* [log in to unmask] or such
> before posting there.
>
> 2. Experiment representatives do not usually read LCG-ROLLOUT mailing
> list, because it is expected to deal with, well, LCG rollout.

I think experiments should avertise their mailing lists. I subscirbed
atlas-lcg months ago but it was on good will basis that I looked around
for more specific lists than lcg-rollout.

> 3. Experiments do run in a production mode. The recent LCG review stated
> that the LCG is far from being in a production state, but I'd like to
> see it proven wrong. So please don't be surprised to see files arranged
> "as if they run production". It's not "if", they *DO* run production,
> and each bit of data is needed in long term (months and years).
> 4. Experiments perceive Storage Elements as *STORAGE* elements. They
> expect the files to stay there. And they can not move them elsewhere.
> Please do not advertise your facility as a Storage Element if it is
> *NOT* a Storage Element.

I do believe that a lot of files left behind are waste that hasn't been
cleaned up by failed jobs and since we are now in a shared environment it
should be good practice of the experiments to periodically and
frequently clean up.

>
> 5. When your Storage Element is full, remove it from the Information
> System, or press the Data Management folks to develop a better solution.
> Do not stop PBS queues, as the jobs may well write to another Storage
> Element, not yours.

> To summarise, we seem to be asked to move our files from nearly
> everywhere. I guess everybody realizes it's very difficult, and BTW,
> we'll be producing 150% of what we have now in nearest 3 months. Thus a
> removal of 7% or what won't help. We really expected the storage
> facilities to be such, esp. Tier1-scale centers.

I think this is more of a problem of data and storage management. Any site
can put what they have but there will be an big variety of hardware to
deal with. I don't see in place neither the software nor a good policy to
use it properly. It's really easy to ask the sites to push the data
management developers to implement features, perhaps it is the experiments
that should do something about it. It's your data after all (on our
machines). It looks like the law of the jungle if jobs don't even check
the storage element space and don't respect any kind of policy.

cheers
alessandra


--
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* Dr Alessandra Forti                      *
* Technical Coordinator - NorthGrid Tier2  *
* http://www.hep.man.ac.uk/u/aforti        *
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