RAL Tier1 Experiments Liaison Meeting

Wednesday 10 Mar 2021, 12:30 → 13:30 Europe/London

Access Grid (RAL R89)

Please attend via the following Zoom meeting:

https://ukri.zoom.us/j/98562731547?pwd=UU9Wb2xCL05tWmROT1h6SUlWdUJ3dz09

 

12:38 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))

RT1EL-20210310.docx

RT1EL-20210310.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

12:42 Experiment Operational Issues

4 VO-Liaison ATLAS

Speakers: James William Walder (Science and Technology Facilities Council STFC (GB)), Dr Tim Adye (Science and Technology Facilities Council STFC (GB))

*  ATLAS needs to run more single-core analysis jobs
- https://helpdesk.gridpp.rl.ac.uk/Ticket/Display.html?id=397775

* ATLAS hostname env for WN containers
- https://helpdesk.gridpp.rl.ac.uk/Ticket/Display.html?id=398494 

* Oxford Xcache; Done on RAL side
- https://helpdesk.gridpp.rl.ac.uk/Ticket/Display.html?id=397191 

 

Discrepancy between Vande 100% CPU (for ATLAS)  and  ATLAS Monitoring (cf. Vande * 11.7/10). 
 - to be understood

ATLAS slowly increasing Single-core running jobs (to ~ 3k).

 

 

Vector Reads:
   CMS Sam test code can run on gw683 and gw691:
- See at what frequency problem can be triggered;
- In parallel try some lower-level tests

 

5 VO Liaison CMS

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

SAM tests are ok, just occasional failures. Transfers seem fine.

However, real jobs are failing at a very high rate. Efficiency is extremely low. CMS L1s have asked me to organise stopping Processing-type jobs running at RAL, as these are the culprits. Failures are 60-80% and efficiencies are <1% for many jobs. These jobs mostly fail with FileOpen or File Read.

I changed the redirector fallback from the UK alias to the European alias. This seemed to reduce the number of FileOpen errors (the total number of failures remained high - FileOpen errors were replaced by FileRead errors). 

6 VO Liaison LHCb

Speaker: Raja Nandakumar (Science and Technology Facilities Council STFC (GB))

7 VO Liaison Others

12:53 Experiment Planning

8 Dune/protoDune

9 Euclid

10 SKA

12:57 AOB

11 Any other Business

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