March 2019 Offline Leads Meeting Notes

The March 2019 LArSoft Offline Leads meeting was handled via email and a google document.

LArSoft – Erica Snider

  • LArSoft Workshop Plans – targeting June 2019 — Planning for the summer LArSoft workshop has begun. We anticipate three sessions, the first of which will be an introduction to LArSoft that will include material from DUNE’s introductory TCP workshop series. This will be followed by a multi-threading and vectorization section targeting CPU-based grid processing, and discussion of HPC resource utilization. The third session will cover the long-term vision for LArSoft and will discuss how LArSoft should evolve as we move toward the era of DUNE data-taking.

Workshop Agenda:

    • LArSoft introduction / tutorial session
      • What should we include? Who is the target audience? What level are we aiming at?
      • Tools to assist in using FHICL?
    • Multi-threading, vectorization, HPC utilization
      • Introduction to multi-threading and vectorization
      • Multi-threading in art
      • Making code thread-safe
      • Experience of a beginner learning to make code thread-safe
      • Vectorizing code
      • HPC computing solutions for LArSoft
    • Long-term vision for LArSoft in the DUNE data-taking era
      • Discuss issues, seek input from experiments, SCD

Please comment and advise on this agenda. Received a suggestion to talk about the impending GitHub migration from the Steering Group. Should we talk about that?

  • The LArTPC Data Overlay Workshop was held on March 4th with the goal of aligning experiments with a common infrastructure and approach to data overlays to be implemented within LArSoft. Key aspects included introducing the overlay method and interested parties, learning from past experience with discussion about adding simulated and data signals, calibrating simulation to match data, timing issues in simulation and data, and producing overlay samples. About 13 people participated in the workshop, including representatives from NOvA, CMS, all LAr experiments, and a theorist. The outcome of the workshop was a list of actions and developments needed for a common data overlay infrastructure, which can be found at the bottom of the meeting notes: The to-do list includes:
    • Port common waveform adding tools to LArSoft (Adi + LArSoft person)
      • Redmine tickets
    • Create art tool interfaces for the various mixers (Adi + DUNE person + LArSoft person)
      • OpDetWaveform
      • RawDigit
      • CRTHit
      • Redmine tickets
    • Investigate whether calibrations should be services or tools (Expts + LArSoft person)
      • The bigger question, which  corrections can be made more generic than they currently are
      • Already built on service interfaces
    • Figure out what to do with the art::Event::isRealData() method (Expts + art person)
      • Need a richer description for overlay data
      • Consider service, more methods, eg, hasRealData/hasMCData, etc
      • Something else
    • Are there general ways to think about timing that preserve the ability to do back-tracking in overlay data samples? (Expts)
    • Consider whether inline (eg, in-situ simulation) vs file-based primary / secondary overlay model is optimal
      • Trade-offs between the need to handle multiple input files vs controlling event re-use
    • Art EventMixing infrastructure needs to be more capable in order to be useful (Expts + art person + LArSoft person)
      • Particularly associations are currently not supported
    • Can we design a standardized way for grid jobs to deal with run/subrun/conditions alignment issues between input files  (FIFE (and Andrei Gaponenko) + ??)
  • Ubuntu support. We wanted to remind offline leads that ubuntu is supported under an “on-demand” model.  It is important that offline leads and users know that they can request ubuntu releases as needed.

DUNE – Andrew John Norman, Heidi Schellman, Tingjun Yang, Tom Junk

We are starting to think about and work on ways to read in partial event data so that an entire Far Detector module’s worth of raw digits aren’t in memory at any given time.  ProtoDUNE-SP has already taken some test data that are broken into several smaller branches (with different module/instance names) which helps the input step. We propose that in the Far Detector, each APA gets a branch of fragments out of artdaq, so that GetByLabel and GetValidHandle don’t immediately reserve large amounts of memory just to get any data in.

ICARUS – Daniele Gibin, (Tracy Usher)

ICARUS is preparing to launch effectively MCC 2 which will provide simulated data for the upcoming SBN Workshop in Oxford the beginning of April. Much progress has been made since MCC 1, the signal processing (with a coherent noise model) is in good shape, we are running the latest pandora track/shower reconstruction plus downstream track fits, we now have the first attempt at an optical reconstruction and are in position to work on the CRT reconstruction. A goal for the workshop will be to try to do track/flash matching. There is still much to do… work is ongoing to extend the photon library to all four TPC’s, we still need to split the horizontal wires, etc.

I would guess that sometime in the Spring ICARUS should be ready to ask for help in doing a timing and memory usage review. Most of the current simulation/reconstruction jobs run fairly quickly but are only single particle or neutrino with no cosmic samples and here we suppress the channels with no MC signal. The CR sim/recon times jump dramatically, handling the >50,000 channels in the TPC alone is significant load. Also, the photon library consumes a fair bit of memory, as does the CRT simulation.

LArIAT – Jonathan Asaadi

No Report

MicroBooNE – Herbert Greenlee, Tracy Usher

No Report

SBND – Andrzej Szelc

Main recent effort has been on optimizing the light simulation, towards trying to understand the impact of the beam rotation change in the BNB on physics analyses. We have implemented an improved optical library (needed adding stash-cache functionality following DUNE example), improved timing parametrization and semi-analytic light simulation (will be used soon). In parallel, we are starting to test the update to nutools implemented by Robert Hatcher, that allows tweaking the beam bucket parameters. Final step is to update the digitization simulation. Once that is done we plan to launch a relatively large data production in order to provide data samples for summer internships and understand the timing resolution.

Please email Katherine Lato or Erica Snider for any corrections or additions to these notes.