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 and EOS space.

Experiment/Group	status Mar 2020	pledge April 2020	pledge April 2021
ATLAS T3 Wisconsin	0.3	0.1	0.1
LHCb T3 CERN	0.2	0.2	0.3
TOTEM	0.6	0.6	0.6
NP02	1	1	2
NP04	1	1	2
Public instance,other	8	12	16
total sum	134	137	174
LHCb	14	17.2	18.8
COMPASS	2	2	3
ATLAS T3 CERN	1.8	2.0	2.4
CMS T3 CERN	2.0	2.2	2.6
CMS	25.6	26.1	30
ATLAS	27.6	27	30
ATLAS T3 Tokyo	3	3	3
ALICE	35.3	31.2	45.5
NA62	4	4	5
AMS	7	7	12
	[PB]	[PB]	[PB]

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%