If this is a one-time fix for a corrupted index, did you look at
CREATE INDEX CONCURRENTLY? You could avoid any down time while you
fix things up.
Using CREATE INDEX CONCURRENTLY will avoid the exclusive locks on the table, but my question is, how to get a performance on the existing indexes. You mean to say , drop the existing indexes and create the index with CONCURRENTLY. Does this give the performance back.
Regards
Raghavendra