Date: Mon, 29 Dec 2025 17:09:22 +0100
From: Christoph Moench-Tegeder <cmt@burggraben.net>
To: pramod gupta <mail2sony2010@gmail.com>
Cc: pgsql-general@postgresql.org
Subject: Re: How did VACUUM ANALYZE reclaim large TOAST bloat at disk level
 in PostgreSQL 16?
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## pramod gupta (mail2sony2010@gmail.com):

> How was VACUUM ANALYZE able to reclaim such a large amount of space,
> especially for TOAST data?
> 
> Under what conditions does PostgreSQL reclaim disk space without requiring
> VACUUM FULL or CLUSTER?

https://www.postgresql.org/docs/current/routine-vacuuming.html#VACUUM-FOR-SPACE-RECOVERY
"in the special case where one or more pages at the end of a table
become entirely free and an exclusive table lock can be easily obtained"

Regards,
Christoph

-- 
Spare Space