I just updated to 1.24wmf21 (2691b4d) (same version as here) from 1.24wmf14 and it started to "Updating *_from_namespace fields in links tables." which takes looong time. If a break it, and restart update.php it just restart the updating of the fields.
Is it possible to break the updating (and not get the updating of the fields again) and just get the new fields when the page is changed or hit the refreshlinks from the job queue?