On Mon, Sep 12, 2016 at 9:17 AM, Patrick B <patrickbakerbr@xxxxxxxxx> wrote:
Hi guys,select schemaname,relname,n_live_tup, n_dead_tup from pg_stat_all_tables where relname = 'parts';schemaname relname n_live_tup n_dead_tup
---------- ------------- ---------- ----------
public parts 191623953 182477402
See the large number of dead_tup?My autovacuum parameters are:"autovacuum_vacuum_threshold" : "300",
"autovacuum_analyze_threshold" : "200",
"autovacuum_vacuum_scale_factor" : "0.005", "autovacuum_analyze_scale_factor" : "0.002", Table size: 68 GBWhy does that happen? Autovacuum shouldn't take care of dead_tuples?
Could you notice if the table is regularly getting vacuumed at all ? when was the last_autovacuum and last_autoanalyze time ?
Because of that the table is very slow...When I do a select on that table it doesn't use an index, for example:\d parts;"index_parts_id" btree (company_id)
"index_parts_id_and_country" btree (company_id, country)explain select * from parts WHERE company_id = 12;Seq Scan on parts (cost=0.00..6685241.40 rows=190478997 width=223)
Filter: (company_id = 12)
That should be due to not running VACUUM and ANALYZE. Did you VACUUM ANALYZE and see if the query is picking up the Index. This is possible if "company_id" has unique values.
Regards,
Venkata B N
Fujitsu Australia
