Queries using GIN index on f_unaccent() seem slow?

I have almost 20M rows in one table that contains product, including their names. I wish to search fulltext and fast by the name so I created this index: CREATE INDEX uprice_item_occurrence_unaccent_name_trgm_idx ON price_item_occurrence USING gin (f_unaccent(name) gin_trgm_ops);; I was hopping the following query would take less then (lets say) 500ms select * from price_item_occurrence as oo where f_unaccent(oo.name) % f_unaccent('iphone'); But it takes almost 2s: postgres=# explain analyze select * from price_item_occurrence as oo where f_unaccent(oo.name) % f_unaccent('iphone'); QUERY PLAN --------------------------------------------------------------------------------------------------------------------------------------------------------------------- Bitmap Heap Scan on price_item_occurrence oo (cost=1956.42..63674.14 rows=16570 width=287) (actual time=247.918..1880.759 rows=94 loops=1) Recheck Cond: (f_unaccent((name)::text) % 'iphone'::text) Rows Removed by Index Recheck: 87838 Heap Blocks: exact=76663 -> Bitmap Index Scan on uprice_item_occurrence_unaccent_name_trgm_idx (cost=0.00..1952.28 rows=16570 width=0) (actual time=195.418..195.418 rows=88962 loops=1) Index Cond: (f_unaccent((name)::text) % 'iphone'::text) Planning time: 0.444 ms Execution time: 1880.833 ms It's possible that the DB is busy, but i am not sure. I tried to play with select set_limit(0.9); (increased) and it helps a bit but not much. I am using Postgres 10, can change the Postgres config and I am open for suggestions. I tried it with ilike and it improved by some: postgres=# explain analyze select * from price_item_occurrence as oo where f_unaccent(oo.name) ilike ('%' || f_unaccent('iphone') || '%'); QUERY PLAN -------------------------------------------------------------------------------------------------------------------------------------------------------------------- Bitmap Heap Scan on price_item_occurrence oo (cost=3135.08..416823.45 rows=166075 width=286) (actual time=50.258..670.085 rows=65917 loops=1) Recheck Cond: (f_unaccent((name)::text) ~~* '%iphone%'::text) Rows Removed by Index Recheck: 10 Heap Blocks: exact=59750 -> Bitmap Index Scan on uprice_item_occurrence_unaccent_name_trgm_idx (cost=0.00..3093.56 rows=166075 width=0) (actual time=37.385..37.385 rows=67700 loops=1) Index Cond: (f_unaccent((name)::text) ~~* '%iphone%'::text) Planning time: 0.545 ms Execution time: 675.776 ms (8 rows) About 2x faster. i tried limit 10: postgres=# explain analyze select * from price_item_occurrence as oo where f_unaccent(oo.name) % f_unaccent('iphone') limit 10; QUERY PLAN -------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Limit (cost=373.27..410.51 rows=10 width=287) (actual time=268.718..589.131 rows=10 loops=1) -> Bitmap Heap Scan on price_item_occurrence oo (cost=373.27..62493.45 rows=16680 width=287) (actual time=268.715..589.123 rows=10 loops=1) Recheck Cond: (f_unaccent((name)::text) % 'iphone'::text) Rows Removed by Index Recheck: 18917 Heap Blocks: exact=17100 -> Bitmap Index Scan on uprice_item_occurrence_unaccent_name_trgm_idx (cost=0.00..369.10 rows=16680 width=0) (actual time=165.958..165.958 rows=69268 loops=1) Index Cond: (f_unaccent((name)::text) % 'iphone'::text) Planning time: 0.397 ms Execution time: 589.187 ms (9 rows) this is also faster, maybe almost good enough