This could in some cases significantly increase the pause times for nursery collections. I haven't confirmed this with any evidence, but I just realized it might be an issue. First step is to investigate. If it proves to be a problem we might be able to rework some things to make it so nursery collections don't need to wait for the compiler to finish what it's doing.
Marking as a duplicate of the other bug since there's more concrete data there. *** This bug has been marked as a duplicate of bug 128291 ***
Is this meant to cover both DFG and FTL compilations? If so, why is it duped to https://bugs.webkit.org/show_bug.cgi?id=128291, which is meant to only cover LLVM-based compilations? I believe that making all compilations concurrent is a significantly harder problem, than reducing the pauses due to LLVM compilations.
I don't think this is the same bug.
I'm gonna re-dup this back to that bug. I think your ultimate solution turned out to solve this issue with both the DFG and FTL. *** This bug has been marked as a duplicate of bug 128291 ***