Data Retention Policy

Space	Size	Backup	Lifetime	Comment
xtc	Unlimited	Tape archive	1 year	Raw data
hdf5	Unlimited	Tape archive	1 year	Data translated to HDF5
scratch	Unlimited	None	1 year	Analysis results and temporary data
User home	Unlimited	Disk + tape	Indefinite	User code
Tape archive	Unlimited	Two copies	10 years	Raw data

Space	Size	Backup	Lifetime	Storage class	Comment
xtc	Unlimited	Tape archive	3 months	Short-term	Raw data
hdf5	Unlimited	Tape archive	3 months	Short-term	Data translated to HDF5
ftc	10TB	None	2 years	Medium-term	Filtered, translated, compressed
res	1TB	Disk	2 years	Medium-term	Analysis results
tmp	Unlimited	None	3 months	Short-term	Temporary data
User home	20GB	Disk + tape	Indefinite		User code
Tape archive	Unlimited	Two copies	10 years	Long-term	Raw data

The main goal of the new proposed policy based on three different storage classes is twofold:

Allow users to have easy access (ie on disk) to the most frequently used data for a longer period of time

Encourage users to filter their data to get rid of useless runs or useless events within a run

The new policy will be accompanied by web tools to facilitate users in:

Applying processing framework to select useful events within a run (only when effective; here we'll need help from users who must decide which events are good)