LArSoft Coordination Meeting

US/Central
Zoom-only

Zoom-only

Description

To connect via Zoom:  Meeting ID 831-443-820

Password distributed with meeting announcement

(See instructions for setting Zoom default to join a meeting with audio and video off: https://larsoft.org/zoom-info/)

PC, Mac, Linux, iOS, Android:  https://fnal.zoom.us/j/831443820

Phone:

H.323:

162.255.37.11 (US West)
162.255.36.11 (US East)
213.19.144.110 (EMEA)
See https://fnal.zoom.us/ for more information
 

At Fermilab:  no in-person presence at the lab for this meeting

 

 

Release and project report

  • Comments:

    • Wes Ketchum: New PR from Pandora?

      • Bug fix for Pandora. Needed by ICARUS.

      • Andy said it was submitted earlier today

      • Lynn Garren: Should go in before the Pandora PRs being discussed today. Is that ok? A: yes.

    • Wes: ICARUS is particularly interested in larsim#44, promote OpFastScintillation methods from protected to public

      • SciSoft saw no issues (although this speaks to architectural problems, so there may be follow-up), so just waiting for L2 approval

 

 

Andy Chappell:  Pandora deep learning pull requests

  • Active requests for larpandoracontent and larpandora add LibTorch support to Pandora

    • relevant libs can be built/linked w cmake/mrb option DPANDORA_LIBTORCH=ON/OFF to larpandoraocontent / larpandora respecitvely, but also checks for presence of libTorch and falls back to std build if missing

    • Default is ...

  • DL lib in pandora

    • Diagram

    • Key additions are LArCLContent and DLMasterAlgorithm

    • DLMasterAlgorithm is a subclass of MasterAlgorithm so registers DL alongside standard algs

 

  • Using the LArDLContent library

    • If no need of LIbTorch, Pandora can be used entirely unchanged, but to use LibTorch functionality, an alternative master algorithm is used: LArDLMaster

    • If the only XML change, everything will run as if the LArMaster algorithm was still in use

      • Useful for validationg the build, while leaving all ouptuchs unchanged

      • When built with -DPANDORA_LIBTORCH=ON, larpandora registers DL algs, which can then be included via top-level XML

    • To use LibTorch-based alg, the alg should live in larpandoradlcontent branch of larpandoracontent repository (in lar_dl_content namespace), and then added to the approp worker XML

  • LibTorch performance implications

    • Investigation on recently observed performance issues when running in LArSoft context is on-going, so currently not undesirable to have DL algs running now.

    • As such, although DL functionality is include by default in these PRs, no perf hit is expected while the LibTorch perf issue is investigated

      • Main aim was just to make this functionality available

      • In near-term, trach/shower discrimination and vertexing networks can be tested w/in existing reco chain

      • Longer-term: investigating use of networks across diff areas of the reco, from clustering through to alg selection

    • Also eager to use GPUaaS

  • Summary

    • PRs provide LIbTorch DL support

    • Goal is to allow functionality for development and testing

    • No performance hit expected from current LibTorch issues

 

  • Patrick Gartung: Update on LibTorch investigation

    • Libtorch will pick the best algorithm based on the CPU it is being run on. The “ups” build disables the inclusion of the mkldnn library for worry that it might cause an illegal instruction on an AMD cpu (eg, on the grid somewhere). PG tried a libtorch build with mkldnn enabled on an AMD cpu system and it fell back to using libopenblas, which has an algorithm that will work with the AMD cpu instruction set. The mkldnn only provides the performance boost on Intel processors with AVX512 registers.

    • So, the speedup seems to be where it uses just in time compilation

    • The good news: Can build it the way Andy built it, and when it lands on the right kind of machine, it will be performant.

    • How often will it be the right machine?

      • Depends. And hard to say for the general case

      • Alex Himmel: Can put something in class ads to require certain instruction sets? Talk to FIFE people

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