We need an estimate of how much data we are talking about. Based on that we can decide if it's Ok to make a year long subscription.

In general, please keep in mind that Tier0 subscriptions are meant to be used as initial subscription, i.e. if user's needs go beyond what T0 rules are providing new Rucio rules should be created by the user.

Hi Dima,

We need an estimate of how much data we are talking about. Based on that we can decide if it's Ok to make a year long subscription.

Ok we'll try to get an estimate asap!
Indeed this was also my concern when I mentioned the possibility to update the diskNodes for these alcarecos.

if user's needs go beyond what T0 rules are providing new Rucio rules should be created by the user.

This is not always true for the express case, since there is not default tape subscription, once the 3 months are over the dataset is deleted for good. E.g. this happened now with:
/StreamExpressAlignment/Run2022B-TkAlMinBias-Express-v1/ALCARECO

Can you clarify why 3 months is not enough to realize that you need the data for longer and you need to make a new subscription? Is it because the data is used only much later? Maybe we should reconsider the idea of having a tape copy? Basically we should not put all data on disk for a year if we just need a small fraction once in a while.

Hi @drkovalskyi
I made this table based on 2022C (so far the largest for 2022 with ~5/fb collected) to give you an example of the sizes.

Can you clarify why 3 months is not enough to realize that you need the data for longer and you need to make a new subscription? Is it because the data is used only much later?

For example the StreamExpressAlignment alcareco I mentioned in my previous message is used to derive the beamspot conditions for the re-reco, so maybe 1 year is an overshoot, but at the same time 3 months is too short...
But I understood (from private conversations) that in Run 2 the policy was to store them for 12 months, so that's what I'm also implementing in this PR.

Maybe we should reconsider the idea of having a tape copy?

Yes I guess this enters in the same general discussion about alcareco handling (see also https://its.cern.ch/jira/browse/CMSTZ-1005)

Basically we should not put all data on disk for a year if we just need a small fraction once in a while.

Are you now referring to T2_CH_CERN or Disk sites in general?

Ok, so we are talking about ~35TB for ~20-25% of data, i.e. it's 100-200TB per year. I think it's small enough to just keep it all for a year.

Thanks Dima!

@germanfgv @jhonatanamado I guess this PR can be merged then.

test syntax please