Re: Parallel Bitmap scans a bit broken

On Thu, Mar 16, 2017 at 5:02 AM, Dilip Kumar <dilipbalaut@gmail.com> wrote:
> After above fix, I am not able to reproduce. Can you give me the
> backtrace of the crash location or the dump?
>
> I am trying on the below commit
>
> commit c5832346625af4193b1242e57e7d13e66a220b38
> Author: Stephen Frost <sfrost@snowman.net>
> Date:   Wed Mar 15 11:19:39 2017 -0400
>
> + https://www.postgresql.org/message-id/attachment/50164/brin-correlation-v3.patch
> + fix_tbm_empty.patch

Forgot to mention after fix I am seeing this output.

postgres=# explain analyze select * from only r2 where i = 10;
                                                          QUERY PLAN
-------------------------------------------------------------------------------------------------------------------------------
 Gather  (cost=2880.56..9251.98 rows=1 width=4) (actual
time=3.857..3.857 rows=0 loops=1)
   Workers Planned: 2
   Workers Launched: 2
   ->  Parallel Bitmap Heap Scan on r2  (cost=1880.56..8251.88 rows=1
width=4) (actual time=0.043..0.043 rows=0 loops=3)
         Recheck Cond: (i = 10)
         ->  Bitmap Index Scan on r2_i_idx  (cost=0.00..1880.56
rows=373694 width=0) (actual time=0.052..0.052 rows=0 loops=1)
               Index Cond: (i = 10)
 Planning time: 0.111 ms
 Execution time: 4.449 ms
(9 rows)

postgres=# select * from only r2 where i = 10;
 i
---
(0 rows)

Are you getting the crash with the same test case?

-- 
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com