slow index creation with gist and gist__int_ops
I have also had this problem, and have never found a solution, other than "don't use gist__int_ops".  The picksplit or penalty function seems to go pathologically wrong on large tables.  I don't know if this is a bug someone could fix with enough effort, or if it is an inherent problem.


  (since it should work better on frequently updated /inserts table)


I don't know how good this advice actually is (or ever was).  Note that it was removed from the docs in version 9.5.  But if you can never get the build to finish anyway, then surely it can't be good advice for your situation.