RAL Tier1 Experiments Liaison Meeting

Wednesday 7 May 2025, 13:30 → 15:50 Europe/London

Access Grid (RAL R89)

13:30 Experiment Operational Issues

1 ATLAS Operations Report

Speakers: Brij Kishor Jashal (Rutherford appelton laboratory), Jyoti Prakash Biswal (Rutherford Appleton Laboratory)

ATLAS liason meeting notes Brij

2 CMS Operations Report

Speaker: Katy Ellis (Science and Technology Facilities Council STFC (GB))

3 LHCb Operations Report

Speaker: Alexander Rogovskiy (Rutherford Appleton Laboratory)

jobs.png

transfers_from.png

transfers_to.png

Issues:

• ECHO instability last Wednesday
  • Resulted in failed transfers/job uploads/downloads, and, most annoyingly, in file loss (GGUS 683184)
    • Due to race conditions between https and root protocols
    • There should be a way to mitigate this, e.g.
      • Poison DNS entry for webdav.echo.stfc.ac.uk on WNs (for LHCb jobs at least), so that it is redirected to local gateway as well
      • Introduce some locking/protection (e.g. do not execute delete if it arrived more than N minutes ago)?

4 ALICE Operations Report

Speaker: Alexander Rogovskiy (Rutherford Appleton Laboratory)

5 LSST Operations Report

Speakers: Mathew Sims, Timothy Noble (Science and Technology Facilities Council STFC (GB))

• LSST jobs from latest pipeline failing,
  • We think currently this is due to the job pulling in the instructions (QG), writing out to echo any changes, then reading locally and complaining its changes were not there. - Contacting Middleware team about this.
• Moving data to 'correct' location on echo, started on Friday and moved 220,000 files so far with originals and copies checksumed and if they matched old one deleted.
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14:00 Tier-1 Projects

6 Anatares Upgrade

New EOS nodes
Tape Robotics downtime

Speakers: George Patargias, Thomas Byrne

7 XRootD Development

Speakers: Alexander Rogovskiy (Rutherford Appleton Laboratory), Jyothish Thomas (STFC)

8 Utilizing GPUs

Speakers: Jyoti Prakash Biswal (Rutherford Appleton Laboratory), Thomas Birkett

14:45 AOB

9 Summary of Operational Status and Issues

Speakers: Brian Davies (Lancaster University (GB)), Darren Moore

Weekly Report 07 May 2025.docx

Weekly Report 07 May 2025.pdf

10 Any other Business

Speakers: Brian Davies (Lancaster University (GB)), Darren Moore