Uh oh!
There was an error while loading. Please reload this page.
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Why do we assume that

4is a good number (other build jobs also do this)?Should we switch to
-j$(nproc)/$(sysctl -n hw.ncpu)?There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
I think that's the number of threads for Linux and Windows.
In this PR, I just copied the other jobs, so this comes from there. We can do the improvements you are suggesting (would also be nicer when running locally with act for eg), but it should probably be in a different PR.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Agreed something for another PR, but worth investigating.
I've sometimes done a test on my fork with different numbers of jobs in a matrix.
For example, with macOS:
make buildbottest TESTOPTS="-j${{ matrix.jobs }} -uall,-cpu"Shows ~4 is about right: