Tuning to speed select
От | Tom Laudeman |
---|---|
Тема | Tuning to speed select |
Дата | |
Msg-id | 44D9E0E3.6010203@virginia.edu обсуждение исходный текст |
Ответы |
Re: Tuning to speed select
Re: Tuning to speed select |
Список | pgsql-general |
Hi, I'm running PostgreSQL version 8 on a dual 2.4GHz Xeon with 1GB of RAM and an IDE hard drive. My big table has around 9 million records. Is there a tuning parameter I can change to increase speed of selects? Clearly, there's already some buffering going on since selecting an indexed ~50,000 records takes 17 seconds on the first try, and only 0.5 seconds on the second try (from pgsql). cowpea=> explain analyze select bs_fk from blast_result where si_fk=11843254; QUERY PLAN -------------------------------------------------------------------------------------------------------------------------------------------- Index Scan using si_fk_index on blast_result (cost=0.00..22874.87 rows=58118 width=4) (actual time=112.249..17472.935 rows=50283 loops=1) Index Cond: (si_fk = 11843254) Total runtime: 17642.522 ms (3 rows) cowpea=> explain analyze select bs_fk from blast_result where si_fk=11843254; QUERY PLAN ---------------------------------------------------------------------------------------------------------------------------------------- Index Scan using si_fk_index on blast_result (cost=0.00..22874.87 rows=58118 width=4) (actual time=0.178..341.643 rows=50283 loops=1) Index Cond: (si_fk = 11843254) Total runtime: 505.011 ms (3 rows) cowpea=> Thanks, Tom -- Tom Laudeman twl8n@virginia.edu (434) 924-2456 http://www.people.virginia.edu/~twl8n/ http://laudeman.com/
В списке pgsql-general по дате отправления: