BGV EOS space

Overview

The EOS folder /eos/bgv is the official repository for the BGV detector data (.mdf, .digi etc files) and data simulated with Gauss/Gaudi. Preferably, only such (large) data files should be stored in this folder.

General info about EOS: basic tutorial, Quick start

• Note: the commands usage examples might be outdated. Working BGV-specific examples can be found below

Discussions and initial setup of the BGV folder took place in the beginning of 2016

• Andreas slides: BGV #76, BGV #77
• Folder Structure:
  • /eos/bgv/
    • data/
      • L0Trigger / {year} / {data}
      • nzs/ {year} / {data}
      • temperature/ {year} / {data}
      • zs/ {year} / {data}

Quota: 5 TB (March 2016)

Usage on LXPLUS

Depending on the user's computing group on AFS, there might be differences in the setup after login to LXPLUS (by default, the LHCb users get a configuration for the LHCb EOS space).

Initial setup (tested with an LHCb computing account (group z5))

BGV EOS space is at the public EOS server, so at every login to lxplus we need to get the configuration:

• source /afs/cern.ch/project/eos/installation/public/etc/setup.sh

After the above command we could also mount the eos public instance in our file system:

• eosmount eos
• this will create a directory eos (relative path) where it mounts the public instance

Command examples

List a directory on eos:

• eos ls -l /eos/bgv

Create and then delete a directory

• eos mkdir /eos/bgv/testdir1
• eos rmdir /eos/bgv/testdir1 OR eos rm -r /eos/bgv/testdir1
• Use "rm" with caution ...

Copy file(s) to eos:

• Using xrdcp
  • xrdcp Run_file.mdf root://eospublic.cern.ch//eos/bgv/data
  • xrdcp Run* root://eospublic.cern.ch//eos/bgv/data
  • Similarly to copy back: xrdcp root://eospublic.cern.ch//eos/bgv/data/2015/raw/Run_file.mdf ~/tmp_data/
• With eos cp
  • Copy Run_file.mdf file to /eos/bgv/ directory: eos cp /eos/bgv/data/2015/Run_file.mdf /eos/bgv/
  • Copy all plain files in /eos/bgv/data/tmp1 to /eos/bgv/data/tmp2/: eos cp /eos/bgv/data/tmp1 /eos/bgv/data/tmp2/
  • Copy the full hierarchy from /var/data/ to /var/data to /eos/foo/user/data/ : eos cp -r /eos/bgv/data/tmp1/ /eos/bgv/data/tmp2/
    • Empty directories won't show up on the target!
  • Remark: If you deal with directories always add a '/' in the end of source or target paths.

Remove file from eos:

• eos rm /eos/bgv/data/2015/Run_file.mdf

Move files on eos:

• Moving files on EOS is not supported by design. The user should first copy, then remove.

EOS man pages:

• man xrdcp, man eos, man eos-cp, etc
• Can be found here (.tar.gz files): /afs/cern.ch/project/eos/installation/public/share/man/man1/

Access string for Gaudi jobs

Read .mdf / .raw files

 
FNameString = "mdf:root://eospublic.cern.ch//eos/bgv/data/20151210/Run_0001378_20151210-180310.bgvctrl.mdf"
EventSelector().Input = [ "DATAFILE='%s' SVC='%s'" %(FNameString, "LHCb::MDFSelector") ]

Read .digi / .dst files (ROOT/POOL format)

 
To be checked ... something like
j.inputdata = ["PFN:root://eoslhcb.cern.ch//eos/lhcb/grid/prod/lhcb/MC/2012/ALLSTREAMS.DST/00038145/0000/00038145_00000008_2.AllStreams.dst"]
or
EventSelector().Input = [ "DATAFILE='root://castorlhcb.cern.ch//castor/cern.ch/grid/lhcb/user/aFile.dst' TYP='POOL_ROOTTREE' OPT='READ'" ]

Usage on the BGV Blade