[postgis-tickets] [PostGIS] #3103: geometry_columns, find_srid performance regress tests

[PostGIS]

#3103: geometry_columns, find_srid performance regress tests
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  Reporter:  robe     |      Owner:  robe
      Type:  task     |     Status:  new
  Priority:  medium   |  Milestone:  PostGIS 2.2.0
 Component:  postgis  |    Version:  2.1.x
Resolution:           |   Keywords:
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Comment (by strk):

 Possibly interesting numbers:

 {{{
 strk=# explain analyze select sum(x) from ( select i::varchar::float8 x
 from generate_series(1,5000000) i ) foo;
 Aggregate  (cost=22.50..22.51 rows=1 width=4) (actual
 time=5743.902..5743.902 rows=1 loops=1)
   ->  Function Scan on generate_series i  (cost=0.00..10.00 rows=1000
 width=4) (actual time=1101.722..2218.290 rows=5000000 loops=1)
 Total runtime: 5823.127 ms
 strk=# explain analyze select sum(x) from ( select i::text::float8 x from
 generate_series(1,5000000) i ) foo;
 Aggregate  (cost=22.50..22.51 rows=1 width=4) (actual
 time=5724.225..5724.225 rows=1 loops=1)
   ->  Function Scan on generate_series i  (cost=0.00..10.00 rows=1000
 width=4) (actual time=1106.496..2226.769 rows=5000000 loops=1)
 Total runtime: 5803.895 ms
 strk=# explain analyze select sum(x) from ( select
 i::varchar::text::float8 x from generate_series(1,5000000) i ) foo;
 Aggregate  (cost=22.50..22.51 rows=1 width=4) (actual
 time=5757.578..5757.578 rows=1 loops=1)
   ->  Function Scan on generate_series i  (cost=0.00..10.00 rows=1000
 width=4) (actual time=1111.779..2228.768 rows=5000000 loops=1)
 Total runtime: 5836.428 ms
 strk=# explain analyze select sum(x) from ( select
 i::text::varchar::float8 x from generate_series(1,5000000) i ) foo;
 Aggregate  (cost=22.50..22.51 rows=1 width=4) (actual
 time=5756.883..5756.883 rows=1 loops=1)
   ->  Function Scan on generate_series i  (cost=0.00..10.00 rows=1000
 width=4) (actual time=1132.671..2249.771 rows=5000000 loops=1)
 Total runtime: 5835.886 ms
 }}}

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/3103#comment:9>
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