Disk Resource Table

This page is for the IT internal planning of disk resources for the LHC experiments, non-LHC experiments and various other groups.

The unit for all disk space number is [PB] and assumes usable disk space (mirrored/replicated). The mentioned amount of space allocated is the SUM of CASTOR/CTA and EOS space.

Policies

1. Usable space is either mirrored RAW space or 2 replicas (conversion factor is 2 between RAW and usable). Any changes in the algorithm or method do not change the pledge values for the experiments in terms of usable space.
2. Special arrangements like the implementation of recycle bins or backup do not change the pledge of disk space. This has to be agreed with the experiment and the total available disk space is always a zero-sum game.
3. The majority of disk space will be available in EOS and only a smaller 'fixed' part in Castor (~10 PB)
4. The precision of the allocated disk space versus the pledge should not be varying more than +-3%