Hello list, DB1=# select version(); -[ RECORD 1 ]---------------------------------------------------------------------------------------------------- version | PostgreSQL 11.5 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-23), 64-bit
I am sure this question has come up before, I have scoured the documentation and I think I have a good grasp on the autovacuum. I wanted to ask the team if my settings for this particular table are too aggressive, I have the following set which is producing a vacuum analyze multiple times a day. I think the defaults out of the box were not aggressive enough, so I went with the following on the global level, I will possibly move to table level if needed. I tried to show the stats below of a 10 minute interval during peak time. Any push in the right direction is appreciated, I want my tables analyzed and vacuumed but do not want to over do it. The rest of the autovacuum settings are default. I know the stats are estimates so here is my calculations. Live tuples = 19,766,480 Analyze scale factor = 0.001 Analyze thresh = 5000 Thresh + live_tuples * factor = 24,766 So an autovacuum analyze should trigger around 24K tuples modified, is this to little or too much? Same goes for autvacuum vacuum, is it too aggressive? #------------------------------------------------------------------------------ # AUTOVACUUM #------------------------------------------------------------------------------ autovacuum_naptime = 1h autovacuum_vacuum_threshold = 10000 autovacuum_analyze_threshold = 5000 autovacuum_vacuum_scale_factor = 0.002 autovacuum_analyze_scale_factor = 0.001 DB1=# \x Expanded display is on. DB1=# select now(); -[ RECORD 1 ]---------------------- now | 2019-11-01 14:35:51.893328-04 DB1=# select * from pg_stat_user_tables where relname = 'members'; -[ RECORD 1 ]-------+------------------------------ relid | 18583 schemaname | public relname | members seq_scan | 129 seq_tup_read | 2036932707 idx_scan | 546161742 idx_tup_fetch | 1670607103 n_tup_ins | 46742 n_tup_upd | 35704112 n_tup_del | 0 n_tup_hot_upd | 31106485 n_live_tup | 19766480 n_dead_tup | 1844251 n_mod_since_analyze | 15191 last_vacuum | 2019-10-13 15:42:06.043385-04 last_autovacuum | 2019-11-01 12:24:45.575283-04 last_analyze | 2019-10-13 15:42:17.370086-04 last_autoanalyze | 2019-11-01 12:25:17.181133-04 vacuum_count | 2 autovacuum_count | 15 analyze_count | 2 autoanalyze_count | 17 DB1=# select now(); -[ RECORD 1 ]---------------------- now | 2019-11-01 14:45:10.845269-04 DB1=# select * from pg_stat_user_tables where relname = 'members'; -[ RECORD 1 ]-------+------------------------------ relid | 18583 schemaname | public relname | members seq_scan | 129 seq_tup_read | 2036932707 idx_scan | 546171120 idx_tup_fetch | 1670615505 n_tup_ins | 46742 n_tup_upd | 35705068 n_tup_del | 0 n_tup_hot_upd | 31107303 n_live_tup | 19766480 n_dead_tup | 1844881 n_mod_since_analyze | 16147 last_vacuum | 2019-10-13 15:42:06.043385-04 last_autovacuum | 2019-11-01 12:24:45.575283-04 last_analyze | 2019-10-13 15:42:17.370086-04 last_autoanalyze | 2019-11-01 12:25:17.181133-04 vacuum_count | 2 autovacuum_count | 15 analyze_count | 2 autoanalyze_count | 17 Thanks for your time, Jason Ralph This message contains confidential information and is intended only for the individual named. If you are not the named addressee you should not disseminate, distribute or copy this e-mail. Please notify the sender immediately by e-mail if you have received this e-mail by mistake and delete this e-mail from your system. E-mail transmission cannot be guaranteed to be secure or error-free as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or contain viruses. The sender therefore does not accept liability for any errors or omissions in the contents of this message, which arise as a result of e-mail transmission. If verification is required please request a hard-copy version.
