Date and time 2021-11-04 15:00UTC (16:00BST)

Action Items

1. Pick Chair and Minuter.
2. ALL: (ongoing) triage the open issues and confirm if they are indeed still open (and perhaps provide labels)

Minutes

Present: CW, KS, LM, NB, SV, JDB, TG, DH

Apologies:

 DH: Mac build disaster

DH: Wrong BLAS getting used in builds sometimes. This can be hard to reproduce.

JDB: Several edits to firedrake-install made when M1 fixes introduced.

Everyone with a Mac: Run firedrake-install (having run brew uninstall openblas) and see if it breaks.

NB: Object versioning

PR: https://github.com/OP2/PyOP2/pull/579

NB: Motivation is to avoid backward propagation when not required. Initially started with Global but has tried to extend to Dat and Mat.

LM: PETSc objects have a state counter that could be exposed from petsc4py. For matrices we could just look at this.

LM: Modifying 'core' parts of iteration set can still invalidate the halo for other partitions. Therefore we should have something that combines halo_valid and object versioning.

Merge PRs:

AOB

Date of next meeting

1500 UTC (1600 BST) 2021-11-11