@Adrian Klaver, I was concerned with the 1.4 value of tbloat and wastedbytes value, then again the last autovacuum was at 2020-02-13 02:25:22.533372-05 and I took this snapshot at 3:44PMEST. So it may be ok, what do you think? current_database | schemaname | tablename | tbloat | wastedbytes | iname | ibloat | wastedibytes notimportant | public | members | 1.4 | 3080314880 | members_cobrid | 0.2 | 0 notimportant=# select * from pg_stat_user_tables where relname = 'members'; -[ RECORD 1 ]-------+------------------------------ relid | 2045245 schemaname | public relname | members seq_scan | 55065 seq_tup_read | 201069350222 idx_scan | 5349501175 idx_tup_fetch | 7201402647 n_tup_ins | 910616 n_tup_upd | 46730942 n_tup_del | 1 n_tup_hot_upd | 41845682 n_live_tup | 18262438 n_dead_tup | 14740 n_mod_since_analyze | 2476 last_vacuum | 2019-10-13 01:01:40.587534-04 last_autovacuum | 2020-02-13 02:25:22.533372-05 last_analyze | 2019-10-13 01:01:41.916929-04 last_autoanalyze | 2020-02-13 13:44:46.273096-05 vacuum_count | 15 autovacuum_count | 92 analyze_count | 15 autoanalyze_count | 243 Jason Ralph -----Original Message----- From: Adrian Klaver <adrian.klaver@xxxxxxxxxxx> Sent: Thursday, February 13, 2020 3:19 PM To: Jason Ralph <jralph@xxxxxxxxxxxxxxxxxxxxx>; Michael Lewis <mlewis@xxxxxxxxxxx> Cc: pgsql-general@xxxxxxxxxxxxxxxxxxxx Subject: Re: pg_upgrade —link does it remove table bloat On 2/13/20 11:07 AM, Jason Ralph wrote: > >There is more than one type of statistics though. Stats on the > distribution of data is easily recreated with analyze table_name or > analyzing the whole >database. What about the stats on how many rows > have been inserted or updated since the last (auto)vacuum and that > will be used to trigger autovacuum? >Are those set back to zero by an > upgrade? I would assume usage counts like how many times an index scan > has been done would be reset, but if the >numbers in > pg_stat_user_tables like n_tup_upd or n_tup_del are zero'd out during > an upgrade, than it would seem like a manual vacuum would always be a > >good idea to ensure a table wasn't 99% of the way to needing one and > then the stats got reset by upgrading. > > I agree @Michael Lewis <mailto:mlewis@xxxxxxxxxxx>, thank you for this > comment. > > I am thinking a vacuum full is what I am going to need. Or pg_dump / > pg_restore. I have tuned auto vacuum after the upgrade to be > aggressive, it finishes fine after a couple hours on a large table, > statistics look good on the pg_stat_user_tables. However, when I run > the bloat check from the wiki > https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwiki > .postgresql.org%2Fwiki%2FShow_database_bloat&data=01%7C01%7Cjralph%40affinitysolutions.com%7C6ead29e3b0bf4238f50e08d7b0c1fd0b%7Cfbf1a257f1104fc19456b0ca3038c6f0%7C1&sdata=d8kSilB5eqJGWujd7tzlX5xaRhm5Z335G34MAO6%2BHOY%3D&reserved=0 it still shows bloat. Thinking it may be left over from before the pg_upgrade and auto vacuum tuning. What values are you getting? The script you are using comes from this: https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbucardo.org%2Fcheck_postgres%2Fcheck_postgres.pl.html%23bloat&data=01%7C01%7Cjralph%40affinitysolutions.com%7C6ead29e3b0bf4238f50e08d7b0c1fd0b%7Cfbf1a257f1104fc19456b0ca3038c6f0%7C1&sdata=XugOdnmx%2BcElhEKTPqL30cjIKEDUyYHl8WvD75r82G8%3D&reserved=0 "If you want to output the bloat ratio instead (how many times larger the relation is compared to how large it should be),..." So I'm pretty sure bloat is where tbloat > 1.0. > > Best, > > *Jason Ralph* > > *From:* Michael Lewis <mlewis@xxxxxxxxxxx> > *Sent:* Thursday, February 13, 2020 1:02 PM > *To:* Adrian Klaver <adrian.klaver@xxxxxxxxxxx> > *Cc:* Jason Ralph <jralph@xxxxxxxxxxxxxxxxxxxxx>; > pgsql-general@xxxxxxxxxxxxxxxxxxxx > *Subject:* Re: pg_upgrade —link does it remove table bloat > > There is more than one type of statistics though. Stats on the > distribution of data is easily recreated with analyze table_name or > analyzing the whole database. What about the stats on how many rows > have been inserted or updated since the last (auto)vacuum and that > will be used to trigger autovacuum? Are those set back to zero by an > upgrade? I would assume usage counts like how many times an index scan > has been done would be reset, but if the numbers in > pg_stat_user_tables like n_tup_upd or n_tup_del are zero'd out during > an upgrade, than it would seem like a manual vacuum would always be a > good idea to ensure a table wasn't 99% of the way to needing one and > then the stats got reset by upgrading. > > 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. -- Adrian Klaver adrian.klaver@xxxxxxxxxxx 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. 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