SpaceTimeStack: Account for MPI imbalance when applying printing threshold

[vbrunini]

So that entries with a low average time but high imbalance are reported since they are often the cause of significant performance problems due to load imbalance.

Also fix missing deep_copy hook exposure.

[vlkale]

…shold.

So that entries with a low average time but high imbalance are reported since they are often the cause of significant performance problems due to load imbalance.

Also fix missing deep_copy hook exposure.

@vbrunini

Thanks for this. I am curious if you can provide an example code with the problem here in the PR description. Even better would be a set of tests via, say, Google Test, to check that those entries with low average time but high imbalance are indeed being reported.

A side note is that the fix for the missing deep_copy hook you have should ideally be a separate PR, as it looks conceptually unrelated to the change related to MPI load imbalance?

Thanks!

[vbrunini]

…shold. So that entries with a low average time but high imbalance are reported since they are often the cause of significant performance problems due to load imbalance. Also fix missing deep_copy hook exposure.

@vbrunini

Thanks for this. I am curious if you can provide an example code with the problem here in the PR description. Even better would be a set of tests via, say, Google Test, to check that those entries with low average time but high imbalance are indeed being reported.

A side note is that the fix for the missing deep_copy hook you have should ideally be a separate PR, as it looks conceptually unrelated to the change related to MPI load imbalance?

Thanks!

Added a test (and split off the deep copy parts into #285)

[vbrunini]

Any suggestions for what to do about the CI failure from the tests running as root?

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