Fix OneDFT MPI double-counting of EXC energy#187
Merged
awvwgk merged 1 commit intowavefunction91:skalafrom Mar 19, 2026
Merged
Conversation
In the OneDFT integrator path, only rank 0 computes the XC energy from the neural network model. The energy is then allreduced with Sum across all MPI ranks. On repeated calls, non-rank-0 ranks still hold the correct energy value from the previous allreduce, causing the Sum to yield 2x the correct value. Fix by zeroing EXC on non-rank-0 processes before the allreduce, so only rank 0's contribution is summed. This affects both the host and device integrator paths. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
awvwgk
approved these changes
Mar 19, 2026
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
In the OneDFT integrator path, only rank 0 computes the XC energy from the neural network model. The energy is then allreduced with
MPI_SUMacross all MPI ranks. On repeated calls, non-rank-0 ranks still hold the correct energy value from the previous allreduce, causing the Sum to yield 2× the correct value.Fix: Zero
EXC[0]on non-rank-0 processes before the allreduce, so only rank 0's contribution is summed. This affects both the host and device integrator paths.This error was actually caught by an MPI test that was failing. Test passes after this edit.