Re: Reindex doesn't eliminate bloat

On 03/12/2018 03:05 PM, Ron Johnson wrote:
> v8.4.12
> 
> According to this (https://pastebin.com/TJB32n5M) query, which I thought 
> I got from https://wiki.postgresql.org/wiki/Index_Maintenance, a list of 
> indexes and their bloat is generated.
> 
> After reindexing a table with a large amount of reported bloat (column 
> bloat_pct says 29%), re-running the query shows no change in the amount 

First I am not seeing a column bloat_pct in the query you linked to, so 
are you sure that is the actual query you used?

> of bloat.  This is a historical table, and VACUUM VERBOSE shows that 
> there's nothing to free up.
> 
> Is this something that I must live with, or am I misinterpreting the query?

Honestly I have not worked my way in depth through the query you show, 
though I did notice it uses pg_stats. What happens if run ANALYZE 
(https://www.postgresql.org/docs/8.4/static/sql-analyze.html) to update 
the stats?

> 
> Thanks,
> 


-- 
Adrian Klaver
adrian.klaver@aklaver.com