HSF Weekly Meeting #152, 29 November, 2018
Present/Contributors: Graeme Stewart, Pere Mato, Serhan Mate, Witek Pokorski, Andrea Valassi, David Lange, Jim Amundson, Torre Wenaus, Ian Collier, Danilo Piparo, Daniel Elvira, Dario Menasce, Tommaso Boccali, Gloria Corti, Paul Laycock, Frank, Caterina Doglioni, Agnieszka Dziurda, Ed Moyse
News, general matters
- IRIS-HEP would like to have HSF representation on their steering
committee.
- Pete Elmer (PI) has proposed that Graeme takes this on.
- Fine with Graeme and got support from others.
- Agreed.
- Gerri Ganis gave the software report to the LHCC
referees this week.
- Questions on licenses and CWP review comments.
- Graeme will give a short report on the new working groups and the generators workshop tomorrow at the WLCG Overview Board.
HSF/WLCG/OSG Workshop
- Meeting took place on Monday 26th to discuss the workshop timetabling.
- Very constructive and we were able to arrive at good range of
substantially shared topics, while also earmarking necessary
separate sessions for WLCG/HSF/OSG matters respectively.
- Draft block timetable being populated here:
- Broad division is 2 days for plenaries with WLCG/OSG, 2 days for HSF parallel sessions.
- Meeting on Thursday 29th to discuss local organisation matters
(immediately after this one).
- Aim today is to fix logistical matters so we can open up registration well before the holidays.
New Working Groups
- Convenors have been appointed - congratulations to them and thanks
to all who took part.
- Detector Simulation: Heather Gray, Witek Pokorski, Gloria Corti
- Reconstruction and Software Trigger: David Lange, Caterina Doglioni, Agnieszka Dziurda
- Data Analysis: Andrea Rizzi, Danilo Piparo, Paul Laycock
- Starting the work of the groups
- Update website (please see instructions)
- Planning for an activity start next year
- HSF “owns” a slot every 2 weeks in 32-1-A24, 17h (odd
weeks):
- 16, 30 January; 13, 27 February
- Sometimes we give over the coordination slot to a topical
meeting, but this room (32-S-C22) is not very good (too
small, no vidyo).
- Pere - equip this room better? Yes please!
- At least one workshop pre-meeting?
- HSF “owns” a slot every 2 weeks in 32-1-A24, 17h (odd
weeks):
- Start to organise a parallel session at the workshop:
- The main theme could be the survey of the existing activities and planned ones in the community.
- Short plenary from each group?
- Contact experiments.
- Mailing lists:
- Probably should have dedicated ones
- Could seed these from the CWP WG lists?
- Reminder that we have the hsf-forum@googlegroups.com (general, everyone) and the hsf-tech-forum@googlegroups.com (technical topics).
- Probably should have dedicated ones
- Convenors should meet together soon.
- Graeme will circulate other names and inputs that we got during the process.
- Short report on plans from each working group in 2 weeks time (December 13).
Generators Software Computing Workshop
- Andrea: Physics Event Generator Computing Workshop took place at
CERN this week
(https://indico.cern.ch/event/751693/timetable/).
Successful workshop, useful discussion and nice atmosphere with a
mix of theorists/experimentalists and a few engineers.
- Many thanks to all the organisers! And to speakers and participants!
- Talks and discussion Mon-Tue and hackathon on Wed.
- Good attendance Mon-Tue (56 people registered), around 30-40 people in person plus 15-20 via vidyo. Smaller attendance (less than 10) at the hackathon, but was also useful.
- Live notes have been taken (by tasked usual suspects, but not only). Some take home messages are at the end.
- We will have a post-mortem probably next week to discuss next steps. A few people (Andrea, Steve) have already agreed to push on work in this area. We might have a dedicated 5-day practical workshop in 2019?
- Graeme will also give a WLCG Overview Board report tomorrow. We forwarded Federico’s invitation to ACAT to generators people. We might also give a summary there (Andy Buckley will be there).
- Some of the take home messages and further work planned:
- Need to continue investigating ATLAS vs CMS differences. Includes Madgraph vs Sherpa but not only. Some comparison numbers were presented by Josh in the ATLAS talk. (Note: LHCb generators mainly concerned with decays rather than production. ALICE were contacted but did not take part in the workshop).
- Need to better understand Run4 projected needs and possible
model. Clear that LO can do unweighted events ok, NLO can
do unweighted events now but only with negative weights
(large penalty as many more events must be generated).
NNLO for the moment is only for differential cross
sections, no unweighted events, but 1-2 orders of
magnitude slower for LO->NLO->NNLO is to be
expected.
- Need some metric to evaluate impact of negative weights, in order to best compare generators.
- The need to coordinate work and reward system between experiments and theorists was pointed out. Example in the Herwig talk “improving code performance would be a lot of work for no recognition”. Also, how to integrate engineers/experimentalists work in theorists’ work? ATLAS/CMS started investigation on recognition for work in generators area.
- Experiment computing infrastructure may help theorists. Example: regression tests for timing and physics performance across code versions. Example: large scale resources for specific NNLO resources.
- Some reports on HPC and GPU work, but not that much work
there.
- David: in the 1.5h HPC session GPUs were not even mentioned.
- In general the HPC work did not show a real need for HPC, this work could have been done also on HTCs.
- GPUs only presented by Madgraph and it was mentioned that at the time they thought the experiments were not interested (or not able to use GPUs). The work was done around 5 years ago by authors that maybe moved elsewhere, but the port should still be functional in principle.
- Some more technical points, e.g. push for common interfaces to apply generator level cuts, review of Les Houches format etc.
- Licensing was mentioned in David’s talk but we kept it intentionally as a side subject. It may be useful to bring this up again in the future though.
Activity updates
Licensing
- Matteo Cacciari was not able to come to CERN, so we are exploring dates early next year to follow up on this. Licensing was raised at the generators workshop and so we may broaden the discussion to the whole theory community.
Packaging
- Meeting 21 November, focusing on Portage tool. Minutes available.
- Next meeting planned for 5 December
Software Development
- Meeting on 6 December on monitoring tools - Servesh will discuss his new Trident tool. N.B. this will replace the usual coordination meeting next week.
Software Forum
- Discussion with the Electron Ion Collider Software
Consortium, 21 November.
- Some interesting topics to follow up on (data formats, analysis workflow) - we could foresee further interactions at the JLab workshop.
- Next meeting on Spark has been expanded to also include a talk from ROOT on Spark - should prove to be fruitful, and we’ll try not to run on too long!
CWP
General Matters and Roadmap
- CWP Roadmap was resubmitted to CSBS.
- Waiting for news from Springer.
Publication status for Individual WG Papers
- Waiting for news from Springer.
- Data Organisation, Management and Access
- Ready to resubmit to arXiv.
- Visualization
- Event/Data Processing Frameworks
- To go to final circulation.
- Facilities and Distributed Computing
- No news.
- Conditions Access
- Paul did a significant revision of the document, hopes to circulate it this weekend.
AOB
- Update: Should we submit a HSF related paper to the European
Strategy Update?
- Pere’s proposal : write a couple of pages around importance of taking software & computing into consideration early in the process of designing new machines/detectors and refer to the CWP for details.
- Pere discussed with Fabiola at the EP faculty meeting and she
did think this was a good idea.
- Graeme, Pere to work on a draft for next week.