RAL Tier1 Experiments Liaison Meeting

Wednesday 12 Jul 2023, 12:30 → 14:30 Europe/London

Access Grid (RAL R89)

13:00 Major Incidents Changes

1 Summary of Operational Status and Issues

Speakers: Brian Davies (Lancaster University (GB)), Darren Moore (Science and Technology Facilities Council STFC (GB)), Kieran Howlett (STFC RAL)

Weekly Report 12 July 2023 (1).docx

Weekly Report 12 July 2023 (1).pdf

2 GGUS /RT Tickets

https://tinyurl.com/T1-GGUS-Open
https://tinyurl.com/T1-GGUS-Closed

3 Site Availability

https://lcgwww.gridpp.rl.ac.uk/utils/availchart/

https://cms-site-readiness.web.cern.ch/cms-site-readiness/SiteReadiness/HTML/SiteReadinessReport.html#T1_UK_RAL

http://hammercloud.cern.ch/hc/app/atlas/siteoverview/?site=RAL-LCG2&startTime=2020-01-29&endTime=2020-02-06&templateType=isGolden

13:05 Experiment Operational Issues

4 VO Liaison CMS

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

writingToCMSdump.pdf

writingToCMSdump.pptx

CMS requested that RAL move to Tape REST API for the metadata features. 

CMS still capped at 6k cores. Performance is good. Tests are broadly green.

Tape transfer issues virtually fixed (see slides). 

5 VO-Liaison ATLAS

Speakers: James William Walder (Science and Technology Facilities Council STFC (GB)), Jyoti Prakash Biswal (Rutherford Appleton Laboratory)

• Survey on Computing for Analysis / Analysis Facilities: https://docs.google.com/forms/d/e/1FAIpQLScYHfpGdeifS3uN0u_jtMIRpIf_H6itQbMK5fVFG9NUBSj8gw/viewform

          (https://stfc.atlassian.net/browse/GRIDPP-1463)

 

File descriptors (https://stfc.atlassian.net/browse/GS-131)
Two nodes in sandboxes for testing

CMSD: Atlas FTS transfers tested behind the redirector; also adding writes from the WNs

 

6 VO Liaison LHCb

Speaker: Alexander Rogovskiy (Rutherford Appleton Laboratory)

plot1207_n.png

plot1207.png

slides.pdf

Tickets:

• Memory limit
  • Memory limit was increased to 12GB, ticket closed
  • Some jobs are still exceeding this, but the number of such jobs is very low
• DNS issue
  • Redirector setup has started last week, looks OK so far
• Slow stats
  • No updates
• Vector read
  • Positive trend persists (2018, 2019, 2020 generations have almost no failures)
  • Production testing with prefetch off should be done
• VO-box certificate
  • No updates

Issues:

• A lot of failed uploads due to gateway restart on Monday
  • Would it be possible to have a downtime for this in future?
• There is a constant low rate of failed downloads from ECHO to RAL's WNs
  • failures mainly come from 2017 generations
  • Could 'prefetch off' help?
• LHCb is draining. All sites are affected

 

7 VO Liaison LSST

Speaker: Timothy John Noble (Science and Technology Facilities Council STFC (GB))

8 VO Liaison Others

13:31 AOB

9 Any other Business

Speakers: Brian Davies (Lancaster University (GB)), Darren Moore (Science and Technology Facilities Council STFC (GB))