https://bugs.winehq.org/show_bug.cgi?id=42512
--- Comment #5 from Sebastian Lackner sebastian@fds-team.de --- (In reply to Anthony Jagers from comment #3)
I you do upload a patch for this, I could use a wine commit tag in the comment to rebase against.
I recommend to test a clean Wine Staging git build (you can get the Wine commit via "patchinstall.sh --upstream-commit") to make sure the performance is back to the original value. There have also been other changes in the meantime, and just applying / reverting a separate change could give misleading results. If you encounter any crashes, try to apply http://source.winehq.org/patches/data/130627 (regression currently present in the dev branch).