Gained %20 performance after disabling bitmapscan

2018-10-19 Thread Yavuz Selim Sertoglu
Hi all, I have a problem with my query. Query always using parallel bitmap heap scan. I've created an index with all where conditions and id but query does not this index and continue to use bitmapscan. So I decided disable bitmap scan for testing. And after that, things became strange. Cost is

Re: Gained %20 performance after disabling bitmapscan

2018-10-19 Thread Justin Pryzby
On Fri, Oct 19, 2018 at 07:19:12AM +, Yavuz Selim Sertoglu wrote: > I have a problem with my query. Query always using parallel bitmap heap scan. > I've created an index with all where conditions and id but query does not > this index and continue to use bitmapscan. So I decided disable bitma

Re: Gained %20 performance after disabling bitmapscan

2018-10-19 Thread Tom Lane
Yavuz Selim Sertoglu writes: > I have a problem with my query. Query always using parallel bitmap heap scan. Have you messed with the parallel cost parameters? It seems a bit surprising that this query wants to use parallelism at all. > Index Cond: (((mukellef_id)::text = '0123456789'::

Re: Gained %20 performance after disabling bitmapscan

2018-10-19 Thread Vladimir Ryabtsev
Yavuz, cannot add much to other points but as for index-only scan, an (auto)vacuum must be run in order to optimizer understand it can utilize index-only scan. Please check if autovacuum was run on the table after index creation and if no, run it manually. Vlad

Re: Gained %20 performance after disabling bitmapscan

2018-10-19 Thread Jeff Janes
On Fri, Oct 19, 2018 at 3:19 AM Yavuz Selim Sertoglu < yavuzselim.serto...@medyasoft.com.tr> wrote: > Hi all, > > I have a problem with my query. Query always using parallel bitmap heap > scan. I've created an index with all where conditions and id but query does > not this index and continue to u