Re: Table bloat threshold limit to trigger repack - Mailing list pgsql-general

From Durgamahesh Manne
Subject Re: Table bloat threshold limit to trigger repack
Date
Msg-id CAJCZkoK_JMcjawyCAGSo8gc8sHad7ugFLZzjuqP2Jmkn_G=Ecw@mail.gmail.com
Whole thread
In response to Re: Table bloat threshold limit to trigger repack  (Ron Johnson <ronljohnsonjr@gmail.com>)
Responses Re: Table bloat threshold limit to trigger repack
Re: Table bloat threshold limit to trigger repack
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On Sun, 8 Feb, 2026, 21:57 Ron Johnson, <ronljohnsonjr@gmail.com> wrote:
On Sun, Feb 8, 2026 at 4:44 AM Durgamahesh Manne <maheshpostgres9@gmail.com> wrote:
On Sun, 8 Feb, 2026, 13:15 Ron Johnson, <ronljohnsonjr@gmail.com> wrote:
On Sun, Feb 8, 2026 at 12:43 AM Durgamahesh Manne <maheshpostgres9@gmail.com> wrote:
On Sun, 8 Feb, 2026, 10:59 Ron Johnson, <ronljohnsonjr@gmail.com> wrote:
On Sat, Feb 7, 2026 at 11:19 PM Durgamahesh Manne <maheshpostgres9@gmail.com> wrote:
Hi

How much table bloat is acceptable before it affects performance in PostgreSQL? 

How big is the table? (For small tables, it doesn't matter.) How active is it?  How frequently are records updated?
 
Hi

Table size 100gb
I use pgstattuple_approx to get Table bloat is about 16gb as of now since after repack is done on 27th of January 
Fillfactor already in place
It's very critical application with updates on non partitioned table 

What did you set the fillfactor to?
Have you minimized the number of indexes?  (That lets HOT work better.)
How long does it take to VACUUM the table?
 
Hi

Fillfactor 80
3 composite and pkey on one column as queries use those 
Vacuum 3min to complete 
Here autovacuum 5min to complete during load even with param tuning 

1. What is autovacuum_vacuum_scale_factor set to?
2. How often does the autovacuum run? (pg_stat_user_tables will tell you.)
3. Do you update any of those indexed columns?
4. How often do queries/reports need to read large chunks of the table (aka sequentially scan it)?
5. Is performance currently suffering, or are you proactively worrying?

Note: Regular vacuuming eliminates bloat.

--
Death to <Redacted>, and butter sauce.
Don't boil me, I'm still alive.
<Redacted> lobster!

Hi 

Periodic maintenance activity already enabled that runs for everyday once 

1).sclae factor for toast 0.06 and non toast 0.1
2).observers that autovacuum runs for every 1hour 
3).2indexed columns are being updated but I think it shouldn't be 
4).most of the time index scan but not sequential scan
5).Seem to be good average latency is less  for queries 
But trying to optimize better than now 

Triggers are already removed 

Any recommendations are welcome 
Please find attached ss
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