Re: [WiP] B-tree page merge during vacuum to reduce index bloat - Mailing list pgsql-hackers

From Madhav Madhusoodanan
Subject Re: [WiP] B-tree page merge during vacuum to reduce index bloat
Date
Msg-id CAKw2Pb3fjYag1MUAHLOx+tj42+UXMKf3xGz9paDCTZuaXPFwZQ@mail.gmail.com
Whole thread
In response to Re: [WiP] B-tree page merge during vacuum to reduce index bloat  (Madhav Madhusoodanan <madhavmadhusoodanan@gmail.com>)
Responses Re: [WiP] B-tree page merge during vacuum to reduce index bloat
List pgsql-hackers
On Fri, Feb 27, 2026 at 2:33 AM Madhav Madhusoodanan
<madhavmadhusoodanan@gmail.com> wrote:
>
> On Tue, Aug 26, 2025 at 2:11 PM Kirk Wolak <wolakk@gmail.com> wrote:
> > I do have a question, one of the IDEAS we discussed was to ADD a new page that combined the 2 pages.
>
> Would the flow then be as follows? Please correct me if I'm wrong:
> Start: Parent page P, with adjacent child pages A -> B -> C -> D.
> Pages B and C are sparse enough and are about to be merged.
> 1: Acquire lock on pages B and C
> 2: Create a new page N, which copies the tuples in pages B and C
> 3: Acquire lock on parent page P, update the separator keys in P,
> release lock on P
> 4: Update pointers such that pages link like so: A -> N -> D
> 5: Release lock on pages B and C
>
> Regards,
>
> Madhav

On a related note, I noticed the same topic on the 2026 projects list
in the Google Summer of Code page. It mentions that a prototype
extension (pg_btree_compact) has been developed. How do I access the
same?

Thanks in advance!

Madhav



pgsql-hackers by date:

Previous
From: Yasuo Honda
Date:
Subject: [PATCH] Fix unexpected loss of DEFERRABLE property after toggling NOT ENFORCED / ENFORCED
Next
From: Michael Paquier
Date:
Subject: Re: Use pg_malloc macros in src/fe_utils