I did check and found it was the bloated size of pg_class which was slowing down the performance.
It got fixed by adding in routine maintenance task. Things are fine now. However, I want to know how come pg_class (system table) get bloated/affected. What could be the possible ways, where i can look into. Due to business impact auto vacuum is off. Sent from Outlook<http://aka.ms/weboutlook> ________________________________ From: Kevin Grittner <kgri...@gmail.com> Sent: Friday, November 18, 2016 3:49 AM To: Alvaro Herrera Cc: dhaval jaiswal; Adrian Klaver; David G. Johnston; pgsql-general@postgresql.org Subject: Re: [GENERAL] pg_class (system) table increasing size. On Thu, Nov 17, 2016 at 3:16 PM, Alvaro Herrera <alvhe...@2ndquadrant.com> wrote: > Looks like you lost the stat data awhile ago (probably due to a server > crash, or pg_stats_reset()) and it never got updated. I suggest doing > "ANALZYE pg_class" to create initial stats; that might prompt autovacuum > to vacuum the table. If the bloat is excessive, vacuuming might take a > very long time, in which case perhaps consider VACUUM FULL (but be very > aware of its consequences first). > > I think it's likely that this has happened to other catalogs as well, so > check the pg_stat_sys_tables view for other entries with all zeroes in > the n_tup_* columns. +1 Also, you may want to review your autovacuum settings to make sure they are aggressive enough. You didn't describe you machine, your workload, or your vacuum regimen, but if it's a large machine you would probably need to raise autovacuum_vacuum_cost limit. And if autovacuum somehow got turned *off* you are likely to have all kinds of problems with bloat, and may need to schedule some down time to get it cleaned up. -- Kevin Grittner EDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company
