Re: [HACKERS] Problem in Parallel Bitmap Heap Scan?

On Wed, Mar 22, 2017 at 5:38 AM, Thomas Munro
<thomas.munro@enterprisedb.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         | 9.1.2.3/810.0.0.0/8         | 10.1.2.3/810.0.0.0/32
|10.1.2.3/810.0.0.0/8         | 10.1.2.3/810.1.0.0/16        | 10.1.2.3/1610.1.2.0/24        | 10.1.2.3/2410.1.2.3/32
    | 10.1.2.310.0.0.0/8         | 11.1.2.3/8192.168.1.0/24     | 192.168.1.226/24192.168.1.0/24     |
192.168.1.255/24192.168.1.0/24    | 192.168.1.0/25192.168.1.0/24     | 192.168.1.255/25192.168.1.0/26     |
192.168.1.22610.0.0.0/8        | 10::/8::ffff:1.2.3.4/128 | ::4.3.2.1/2410:23::f1/128      |
10:23::f1/6410:23::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
BitmapHeap 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)Planningtime: 0.113 msExecution time: 5.691 ms
 
(13 rows)


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