Comment made by: alexmiller
The title of this ticket is "Optimise argument boxing during reflection". That is a solution, not a problem. What I'm looking for is a title like "Reflection with boxed args is slow" and a description that starts with some example code demonstrating the problem. (That example code often makes for a particularly good template for a test that should be in the patch as well.)
I am then looking for evidence that the change you are suggesting improves the problem. For a performance issue, I am specifically looking for a before/after benchmark, preferably using a testing tool like criterium that gives me some confidence that the gains are real.
From a prioritization standpoint, I do not consider reflection performance to be a high priority because the best answer is probably: don't use reflection. That said, I'm willing to consider it, particularly if there is a compelling example where it may be difficult to remove the reflection or where it is particularly non-obvious that the reflection is happening.
Regarding your final question, we prefer to consider individual problems rather "a big bunch of changes", so separate would be better.