---
# System prepended metadata

title: HPC Monthly Call -- 2020-09-03
tags: [HPC]

---

HPC Monthly Call -- 2020-09-03
===

###### tags: `HPC`

:::info
- **Date:** September 3rd, 2020
- **Agenda**
- **Participants:**
    - Valentin Churavy, JuliaLab, MIT
    - Elliot Saba, Julia Computing
    - Simon Byrne, CliMA project/Caltech
    - Todd Gamblin, LLNL & Spack
    - Ngoc Nguyen, MIT
    - Chris de Graaf, JuliaLab
    - Albert Reuther, Lincoln Labs, MIT
    - Chris Hill, MIT
    - Bart Janssens, Royal Military Academy Belgium
    - Mose Giordano, UCL

- [Next notes](/@juliaparallel/2019-09-23)
:::


## Summary of last meeting
### Challenges
- Optimized binaries for clusters
- MPI ABI and incompatibilities between Vendors
- Transitive dependency, i.e. MPI used by C/C++ libraries

## Notes

- Add MPI as an ABI to BinaryBuilder?
- Polymorph MPI ABI from OpenMPI to Vendor X MPI
- Japanese MPIAdapter (K-Computer @ RIKEN)
- Convert Project.toml/Manifest.toml to Spack.yaml to generate and build an HPC optimized environment. 
    - How do we “subvert” Julia to then use those Spack generated binaries
    - Overrrides.toml?
    - Old prototype for Summit
        - https://github.com/JuliaLabs/julia-on-summit/blob/master/gen_overrides.jl
        - https://github.com/JuliaLabs/julia-on-summit/blob/master/collect_lmods.jl
    - Endusers & cluster administrators/system engineers
        - Offline tool for system administrators
        - Spackify a global depot
        - How do you limit the hit of loading precompiled files on 100’s of nodes / stop DDOS’ing your filesystem
          https://github.com/hpc/spindle
        - Blessed global depot + user specific environments
    - How does Julia store information about what is being used
        - Content hashing
        - How do you decide which ABI to download
            - Depends on Julia was built
        - Julia & Python
