Re: performance penalty between Postgresql 8.3.8 and 8.4.1

---

Von: Thom Brown [mailto:thombrown@gmail.com]
Gesendet: Dienstag, 8. Dezember 2009 11:12
An: Schmitz, David
Cc: Andres Freund; pgsql-performance@postgresql.org
Betreff: Re: [PERFORM] performance penalty between Postgresql 8.3.8 and 8.4.1

2009/12/8 Schmitz, David <david.schmitz@harman.com>

Hi Andres,

EXPLAIN ANALYZE
select ah.ORDER8_ID, ah.BUILTUP_ID, rl.LINK_ID, la.SIDE,
                   rl.ROAD_NAME_ID, rl.LEFT_ADDRESS_RANGE_ID, rl.RIGHT_ADDRESS_RANGE_ID,
                   rl.IS_EXIT_NAME, rl.EXPLICATABLE, rl.IS_JUNCTION_NAME,
                   rl.IS_NAME_ON_ROADSIGN, rl.IS_POSTAL_NAME, rl.IS_STALE_NAME,
                   rl.IS_VANITY_NAME, rl.ROAD_LINK_ID, rn.STREET_NAME,
                   rn.ROUTE_TYPE
               from rdf.xdf_ADMIN_HIERARCHY ah
               join xdf.xdf_LINK_ADMIN la
               on ah.ADMIN_PLACE_ID = la.ADMIN_PLACE_ID
               join xdf.xdf_ROAD_LINK rl
               on la.LINK_ID = rl.LINK_ID
               join xdf.xdf_ROAD_NAME rn
               on rl.ROAD_NAME_ID = rn.ROAD_NAME_ID
               where rl.IS_EXIT_NAME = 'N'
                   and rl.IS_JUNCTION_NAME = 'N'
                   and rn.ROAD_NAME_ID between 158348561  and 158348660
               order by rl.ROAD_NAME_ID, ah.ORDER8_ID, ah.BUILTUP_ID, rl.LINK_ID;

On Postgresql 8.4.1

Sort  (cost=129346.71..129498.64 rows=60772 width=61) (actual time=100.358..100.496 rows=1444 loops=1)

 Sort Key: rl.road_name_id, ah.order8_id, ah.builtup_id, rl.link_id

 Sort Method:  quicksort  Memory: 252kB
 ->  Hash Join  (cost=2603.57..124518.03 rows=60772 width=61) (actual time=62.359..97.268 rows=1444 loops=1)

       Hash Cond: (la.admin_place_id = ah.admin_place_id)

       ->  Nested Loop  (cost=6.82..120781.81 rows=60772 width=57) (actual time=0.318..33.600 rows=1444 loops=1)
             ->  Nested Loop  (cost=6.82..72383.98 rows=21451 width=51) (actual time=0.232..12.359 rows=722 loops=1)
                   ->  Index Scan using pk_xdf_road_name on xdf_road_name rn  (cost=0.00..11.24 rows=97 width=21) (actual time=0.117..0.185 rows=100 loops=1)

                         Index Cond: ((road_name_id >= 158348561) AND (road_name_id <= 158348660))

                   ->  Bitmap Heap Scan on xdf_road_link rl  (cost=6.82..743.34 rows=222 width=34) (actual time=0.025..0.115 rows=7 loops=100)

                         Recheck Cond: (rl.road_name_id = rn.road_name_id)
                         Filter: ((rl.is_exit_name = 'N'::bpchar) AND (rl.is_junction_name = 'N'::bpchar))

                         ->  Bitmap Index Scan on nx_xdfroadlink_roadnameid  (cost=0.00..6.76 rows=222 width=0) (actual time=0.008..0.008 rows=7 loops=100)

                               Index Cond: (rl.road_name_id = rn.road_name_id)

             ->  Index Scan using nx_xdflinkadmin_linkid on xdf_link_admin la  (cost=0.00..2.22 rows=3 width=10) (actual time=0.023..0.028 rows=2 loops=722)

                   Index Cond: (la.link_id = rl.link_id)

       ->  Hash  (cost=1544.11..1544.11 rows=84211 width=12) (actual time=61.924..61.924 rows=84211 loops=1)
             ->  Seq Scan on xdf_admin_hierarchy ah  (cost=0.00..1544.11 rows=84211 width=12) (actual time=0.017..33.442 rows=84211 loops=1)
Total runtime: 101.446 ms


and on Postgresql  8.3.8:

Sort  (cost=3792.75..3792.95 rows=81 width=61) (actual time=28.928..29.074 rows=1444 loops=1)

 Sort Key: rl.road_name_id, ah.order8_id, ah.builtup_id, rl.link_id

 Sort Method:  quicksort  Memory: 252kB
 ->  Nested Loop  (cost=21.00..3790.18 rows=81 width=61) (actual time=0.210..26.098 rows=1444 loops=1)
       ->  Nested Loop  (cost=21.00..3766.73 rows=81 width=57) (actual time=0.172..19.148 rows=1444 loops=1)
             ->  Nested Loop  (cost=21.00..3733.04 rows=14 width=51) (actual time=0.129..6.126 rows=722 loops=1)
                   ->  Index Scan using pk_xdf_road_name on xdf_road_name rn  (cost=0.00..8.32 rows=1 width=21) (actual time=0.059..0.117 rows=100 loops=1)

                         Index Cond: ((road_name_id >= 158348561) AND (road_name_id <= 158348660))

                   ->  Bitmap Heap Scan on xdf_road_link rl  (cost=21.00..3711.97 rows=1020 width=34) (actual time=0.015..0.055 rows=7 loops=100)

                         Recheck Cond: (rl.road_name_id = rn.road_name_id)
                         Filter: ((rl.is_exit_name = 'N'::bpchar) AND (rl.is_junction_name = 'N'::bpchar))

                         ->  Bitmap Index Scan on nx_xdfroadlink_roadnameid  (cost=0.00..20.75 rows=1020 width=0) (actual time=0.007..0.007 rows=7 loops=100)

                               Index Cond: (rl.road_name_id = rn.road_name_id)

             ->  Index Scan using nx_xdflinkadmin_linkid on xdf_link_admin la  (cost=0.00..2.31 rows=8 width=10) (actual time=0.014..0.017 rows=2 loops=722)

                   Index Cond: (la.link_id = rl.link_id)

       ->  Index Scan using pk_xdf_admin_hierarchy on xdf_admin_hierarchy ah  (cost=0.00..0.28 rows=1 width=12) (actual time=0.003..0.004 rows=1 loops=1444)

             Index Cond: (ah.admin_place_id = la.admin_place_id)

Total runtime: 29.366 ms

Hope this gives any clue. Or did I missunderstand you?

Regards

David


>-----Ursprüngliche Nachricht-----
>Von: Andres Freund [mailto:andres@anarazel.de]
>Gesendet: Dienstag, 8. Dezember 2009 00:25
>An: pgsql-performance@postgresql.org
>Cc: Schmitz, David
>Betreff: Re: [PERFORM] performance penalty between Postgresql

>8.3.8 and 8.4.1
>

>Hi David,
>
>On Monday 07 December 2009 23:05:14 Schmitz, David wrote:
>> With our data it is a performance difference from 1h16min
>(8.3.8) to
>> 2h43min (8.4.1)
>Can you afford a explain analyze run overnight or so for both?
>
>Andres
>

Your output shows that the xdf_admin_hierarchy tables between versions are drastically different.  8.3.8 only contains 1 row, whereas 8.4.1 contains 84211 rows.

Thom