Re: Problem in Parallel Bitmap Heap Scan?

On Wed, Mar 22, 2017 at 5:38 AM, Thomas Munro
<thomas(dot)munro(at)enterprisedb(dot)com> wrote:
> Isn't that one row short? What happened to this one?
>
> 10.0.0.0/8 | 10::/8

Actually, In my last test I did not connect to regression database, I
have simply taken table and the few rows from inet.sql so it was only
16 rows even with seqscan.

Here are the updated results when I connect to regression database and re-test.

regression=# SELECT * FROM inet_tbl WHERE i <> '192.168.1.0/24'::cidr
ORDER BY i;
c | i
--------------------+------------------
10.0.0.0/8 | 9.1.2.3/8
10.0.0.0/8 | 10.1.2.3/8
10.0.0.0/32 | 10.1.2.3/8
10.0.0.0/8 | 10.1.2.3/8
10.1.0.0/16 | 10.1.2.3/16
10.1.2.0/24 | 10.1.2.3/24
10.1.2.3/32 | 10.1.2.3
10.0.0.0/8 | 11.1.2.3/8
192.168.1.0/24 | 192.168.1.226/24
192.168.1.0/24 | 192.168.1.255/24
192.168.1.0/24 | 192.168.1.0/25
192.168.1.0/24 | 192.168.1.255/25
192.168.1.0/26 | 192.168.1.226
10.0.0.0/8 | 10::/8
::ffff:1.2.3.4/128 | ::4.3.2.1/24
10:23::f1/128 | 10:23::f1/64
10:23::8000/113 | 10:23::ffff
(17 rows)

regression=# explain analyze SELECT * FROM inet_tbl WHERE i <>
'192.168.1.0/24'::cidr
ORDER BY i;
QUERY PLAN
-----------------------------------------------------------------------------------------------------------------------------------
Gather Merge (cost=16.57..16.67 rows=10 width=64) (actual
time=4.972..4.983 rows=17 loops=1)
Workers Planned: 1
Workers Launched: 1
-> Sort (cost=16.56..16.58 rows=10 width=64) (actual
time=0.107..0.110 rows=8 loops=2)
Sort Key: i
Sort Method: quicksort Memory: 26kB
-> Parallel Bitmap Heap Scan on inet_tbl (cost=12.26..16.39
rows=10 width=64) (actual time=0.051..0.053 rows=8 loops=2)
Recheck Cond: (i <> '192.168.1.0/24'::inet)
Heap Blocks: exact=1
-> Bitmap Index Scan on inet_idx3 (cost=0.00..12.26
rows=17 width=0) (actual time=0.016..0.016 rows=17 loops=1)
Index Cond: (i <> '192.168.1.0/24'::inet)
Planning time: 0.113 ms
Execution time: 5.691 ms
(13 rows)

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