Difference between revisions of "OWG meeting 18-Apr-2008"
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* Announcements | * Announcements | ||
* Review of minutes from [[OWG meeting 11-Apr-2008|11-Apr-2008]] meeting | * Review of minutes from [[OWG meeting 11-Apr-2008|11-Apr-2008]] meeting | ||
− | * [[ | + | * [[Media:Graham EMU 18-apr-2008.ppt|CODA3 components:]] EMU - Graham |
* [[http://www.jlab.org/~somov/flt_04_18_04.pdf More on event size study]] - Alex S. | * [[http://www.jlab.org/~somov/flt_04_18_04.pdf More on event size study]] - Alex S. | ||
* Status of writing assignments and other preparations for subsystem review - many people | * Status of writing assignments and other preparations for subsystem review - many people |
Revision as of 10:32, 21 April 2008
Contents
Agenda
- Announcements
- Review of minutes from 11-Apr-2008 meeting
- CODA3 components: EMU - Graham
- [More on event size study] - Alex S.
- Status of writing assignments and other preparations for subsystem review - many people
- Electronics - Status of documentation - Fernando
Time/Location
Note special time - 10am Fri 18-Apr-2008 CC F326
Due to scheduling problems, this will be a joint meeting with the Electronics group.
Announcements
Subsystem review will be Wed,Thurs 7,8-May. GlueX collaboration meeting scheduled for the end of that week.
Information concerning the charge, agenda, dry run schedule, etc. can be found on the May 2008 Subsystem Review page.
Elke's Deadlines
- Final presentations to Elke: 5-May close-of-business
- Pre-brief material to reviewers: 30-April
- Pre-brief material to Hall-D group to read: 23-April
- Pre-brief outlines: 11-April
Next Meeting
May not happen due to dry runs
New Action Items from this Meeting
Minutes
Attendees: Elliott W, Ben R, Dave A, Simon T, Beni Z, Dave D, Time W, Chris C, Eugene C, Mark I, David L, Graham H, Ed J, Carl T, Vardan G, Elke A, Elton S, Hai D, Alex S, Jim S, Fernando B.
May Subsystem Review
- Dry run schedule posted on May 2008 Subsystem Review.
- Schedule reordered in order Electronics, Trigger, DAQ, Integration.
CODA3 and EMU Design
Graham outlined the CODA 3 architecture and the discussed role of the Event Management Unit (EMU).
- CODA3 = software toolkit plus hardware recommendations.
- Graham presented history of versions 1 and 2 of CODA, starting in the early 1990's.
- Version 3 for upgrade, includes lessons learned over past decade.
- V2 max 32 crates, single event builder, VxWorks only in ROCs, one event recorder, no pipleline readout, etc.
- V3 no crate limit, multiple/parallel event builders, Linux in ROCs, multiple event recorder, pipelined/blocked readout, etc.
- Do no want to lock into any particular technology for CODA3, use framework + plugin strategy.
- EMU (Event Management Unit) framework for event building/manipulation.
- Uses XML extensively for configuration (input, output, which plugins to use, etc).
- Plug-ins: read, send, store, build, L3.
- Original EMU in C++, Java version in progress.
- We discussed a number of event building architectures and crossbar strategies.
- Can load-balance via crossbar configuration.
- EMU flexible, adaptable to multi-core era.
- EMU prototypes being tested, no real event building yet, but architecture working.
- Full test on LQCD cluster in Sep.
- We had a discussion on blocked readout in front-ends and where this should be disentangled.
Update on Event Rate/Size Study
Alex gave an update from his report last week. See link above for many details.
- Considered signal plus EM and hadronic backgrounds.
- EM using 100 ns gate, 1.1 MeV photon cutoff.
- Used simple cuts. Original CNU cuts tuned w/o EM background so not very effective, need updating.
- EM 78% have no ST signal, hadr 98% have ST signal.
- 93% overall hadr efficience w/Alex's cuts.
- 82 kHz EM plus 98 kHz hadr = 180 kHz total L1 trigger rate with Alex's cuts.
- This work adequate for May review.
Electronics Update
- A lot of background material for pre-brief can be found on the Electronics page.
- Information on grounding in preparation.
- Overview document coming.