GlueX Containers Meeting, March 30, 2018
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GlueX Containers Meeting
Friday, March 30, 2018
11:30 am EDT
JLab: CEBAF Center L207
BlueJeans: 968 592 007
Agenda
- Notes from last Containers Meeting
- Talk to OSG All-Hands Meeting, Monday, March 19.
Notes
Present: Sean Dobbs, Mark Ito, Thomas Britton, Beni Zihlmann, Zisis Papandreau, David Lawrence, Richard Jones
- Atlas and CMS and OSG et al. designed a grid to do raw data reconstruction.
- MC was not considered a problem
- The tiered system has as a component the raw data distribution system
- software and databases were staged as "image files"
- XROOTD
- originally developed at SLAC
- redirector: directory service, contains meta data (file locations)
- on the local host open a file just like a local file except file name is replaced with a URL like root://<name of catalog><IP name of redirector><file name>, triggers an open over network
- redirector refers opener to site, a data connection is opened on site, data streamed over connection
- our bandwidth requirements should be OK
- David: at NERSC, 64 threads on a single node, reconstruction, 4 MB/s read rate
- there is a caching system, if everything is mostly working cache, is not heavily used
- UConn demo system
- redirector service started
- 50 servers, each serving a few files
- 10 Gb pipe
- Client side responsibilities
- download and build XROOTD
- set-up ld_preload[?]
- open calls get intercepted and redirected to XROOTD system
- Sean has also messed with setting up an XROOTD server
- David mentioned the XROOTD idea to Amber Boehnlein, she seems supportive
- Consensus that it would be best if infrastructure supported at JLab on the submit host
- Could be used for both raw data and random trigger files
- Richard and Thomas will work on staging random triggers on UConn demo system
- David: Chip may allow Physics to use 5% of future LQCD KNL cluster
- David: planning for summer campaign at NERSC, reconstruction
- Sean: candidates for off-site resource campaigns:
- ρ and ω yield measurements with 10 or 20 files per run
- 2017 data: 2 periods, low intensity and high intensity
- 2018 data: 4 periods
- Sean: candidates for off-site resource campaigns: