CERN IT Department

CH-1211 Genève 23

Switzerlandwww.cern.ch/

it

Castor development status

Alberto Pace

LCG-LHCC Referees Meeting, May 5th, 2008

DRAFT FOR COMMENTS

http://indico.cern.ch/conferenceDisplay.py?confId=27533

CERN IT Department

CH-1211 Genève 23

Switzerlandwww.cern.ch/

it

Castor status

• The current version of Castor is able to sustain the dataflow from the experiments– Data migration to tapes– Data replication to Tier 1s

• A new consolidated version (2.1.7) is released– Several bug fixes– Better logging

CERN IT Department

CH-1211 Genève 23

Switzerlandwww.cern.ch/

it

Areas of improvement

• Castor Security– Partially implemented since 2.1.6, complete

implementation in progress– Deployment expected 2nd half 2008

• Tape area– Avoid interferences between end-user file

requests (recall of data from tape) and the main experiment data streams and replications• Tape requests will be prioritized

– Tape prioritization will guarantee production• it may have a performance impact on the end-users

wishing to recall files for analysis

CERN IT Department

CH-1211 Genève 23

Switzerlandwww.cern.ch/

it

Impact on future analysis

• We are thinking of possible architectures to ease future data analysis– avoid on-demand file recalls, concept of

“datasets”, recent data always on disk– client protocol status and evolution– impact of strong authentication on scalability– Accessibility of internal performance counters

• An architecture working group is working on these questions– Some proposals are expected before this

summer– See D. Duellmann presentation at Hepix this

Wednesday