I don't see a reason anyone would want to use the unindexed 'revision' vs 'revision_userindex'. We can rename 'revision' to revision_noindex, and revision_userindex to revision.
Same for the logging table.
The problem this causes is tools/users running queries on revision without reading the docs about revision_userindex, and both getting terrible performance themselves and slowing down the server as well.
Version: unspecified
Severity: normal