Go to the Indico Home Page Oldest event Older event Up to category Newer event Newest event Printable version
  • Compact style
  • Indico style
  • Indico style - inline minutes
  • Indico style - numbered
  • Indico style - numbered + minutes
  • Indico Weeks View
    • Switch to the management area of this event
    Login

    EDM4hep Discussion

    → Europe/Zurich
    Zoom

    Zoom
    Live Notes
    EDM4hep Discussion
    Zoom Meeting ID
    98484040528
    Host
    Andre Sailer
    Useful links
    Join via phone
    Zoom URL
    Hide

    EDM4hep Live Notes
    ==================

    Date: June 1, 2021
    Indico: https://indico.cern.ch/event/1044074/
    This is a document for taking notes during EDM4hep meetings.

    Connected: Benedikt, Andre, Thomas, Tao, Zou, Wenxing, Frank, Clement, Gerri, Valentin, Juraj, Graeme, Sanghyun, Joseph

    Apologies: Placido

    ## Introduction and General Points

    * vCHEP
        * Paper re-submission deadline: June 04 (Friday)

    * EPS
    https://www.eps-hep2021.eu/programme/
        * Abstract submitted

    ## Progress and Discussion

    ## Podio

    ###  Support for multiple input sources in parallel
    * https://github.com/AIDASoft/podio/issues/190
    * Please read and maybe comment
    * Presentation by Benedikt at next meeting

    ### Benchmarking

    * Discuss how to integrate with validation in Key4hep

    ### Issues/PRs

    * Fixed width integer types
        * https://github.com/key4hep/EDM4hep/issues/112
        * Needs a bit of adaptation for code generation
        * Merged
        * Move to fixed width types in edm4hep?
            * Makes sense and "doesn't hurt us".
        * Doubles/floats? Are they are guaranteed to be fixed size?
            * standard defines only minimum width
            * `<cstdint>` available for floats?
            

    * Root performance fixes
        * https://github.com/AIDASoft/podio/pull/180
        * Merged

    * Number of fixes [WIP]:
        * https://github.com/AIDASoft/podio/pull/177
        * Pulled apart into smaller PRs:
            * https://github.com/AIDASoft/podio/pull/193
                * Not working with ROOT 6.20/04 and older
                * New (stable) pyroot in 6.22 (to be confirmed?)
                * Merged
                * Propagation of "const" to python? `Const` classes are there only for making things const in python (or were in the past)
                * Check if this is still necessary.
            * https://github.com/AIDASoft/podio/pull/192
                * Merged
                
        * Reference collections not yet "ported". 

    #### Constness in python
    * Currently solved by `Const` classes
    * Also useful for `auto` type deduction, where `const auto` can be necessary otherwise to get something fully correct
    * LCIO solved with flag in collections
    * Do we need python writing?
        * probably yes, for writing ntuple like data

    #### Make a tag after all the warnings are fixed

    #### Heap-use-after-free

    * https://github.com/AIDASoft/podio/issues/174
    * Not a problem in frameworks, but if collections used outside of them
    * Deep inside the memory management of podio, so not easy to fix
    * Happens more often with clang than with gcc, but could be compiler options.
        * Flagged by address-sanitizer
    * Maybe requires deep changes. Change for reference counting of object classes.

    #### c++ concepts
    * BH: add compile time checks for class behaviours: e.g., movable

    #### issue w/ ROOT and (vectors of) non-copyable collections
    * happens in ROOT 6.22 
    * PM: there is a patch available in LCG repository
        * ROOT team is working on a general solution

    #### What are the different branches in the root file?
    * https://github.com/AIDASoft/podio/issues/169
    * Encode more information in the _relation_ branch names?
    * Related to use in RDataFrame/RNTupe, directly looking at root file content
    * Are branch names an implementation detail?
    * backward compatibility "Impossible" (?)

    #### Schema Evolution
    - https://github.com/AIDASoft/podio/issues/86
    - Discussion: https://indico.cern.ch/event/1030566/

    #### Multi-Threading

    #### "event class" in podio

    * Currently being perceived

    ### PRs
    * https://github.com/AIDASoft/podio/pulls

    ### Meta Data

    #### Usage of "metadata" for user defined data
    * need to check if current implementation addresses all use cases
    * need test use-cases

    ### EventStore

    ### Features

    * Subset collections?

    #### framework ROOTWriter
    * Could be refactored to use more standalone things via Gaudi Tools and Services
    * Could potentially more easily write `std::vector`s or other "generic" types
        * Ideally put "generic" data types also in standalone podio
        * How to best allow for "extensions" to an EDM? 
        
    ## LCIOConverters
    * https://github.com/key4hep/k4LCIOReader

    ## EDM4hep
    https://github.com/key4hep/EDM4hep/pulls


    ### MCParticle Endpoint
    * https://github.com/key4hep/EDM4hep/issues/113
    * Keep podio simple by not allowing getters/setters to access multiple internal states. Use utility functions for this use case, if needed.


    ### EDM4hep tools
    https://github.com/key4hep/EDM4hep-utils

    ### Issues

    ## AOB

    ### Next meeting:

    * June 15, 2021

     
    There are minutes attached to this event. Show them.
      • 09:00 → 09:05
        Introduction 5m
        Speakers: Andre Sailer (CERN), Frank-Dieter Gaede (Deutsches Elektronen-Synchrotron (DE))
        EDM4hep Github
        Podio Github
      • 10:00 → 10:01
        Discussion 1m
        Speaker: Dr All