Re: The Free Space Map: Problems and Opportunities - Mailing list pgsql-hackers

From Peter Geoghegan
Subject Re: The Free Space Map: Problems and Opportunities
Date
Msg-id CAH2-Wzm1jUnK-BySw+7doYvsg8k7QGuqwg7kq9XEJzPnRR_vcg@mail.gmail.com
Whole thread Raw
In response to Re: The Free Space Map: Problems and Opportunities  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: The Free Space Map: Problems and Opportunities  (Robert Haas <robertmhaas@gmail.com>)
List pgsql-hackers
On Fri, Aug 20, 2021 at 9:03 AM Robert Haas <robertmhaas@gmail.com> wrote:
> That could be the right decision, but nothing said up to this point
> really seems to suggest it. The open/closed distinction and the
> changes in how to bin available space could all be done with the
> present model.

I guess that's true. Isn't this just semantics, though?

The new FSM implementation certainly cannot forget about pages that it
deems open, or fail to have information about pages that should be
considered open -- that would be absolutely unacceptable. And the
implementation cannot assume that it won't have to maintain
information about every single heap page. All I'm saying is that in
practice this will be very rare. Making the FSM structure smaller
isn't really the goal, though.

-- 
Peter Geoghegan



pgsql-hackers by date:

Previous
From: "David G. Johnston"
Date:
Subject: Re: Improving some plpgsql error messages
Next
From: Ranier Vilela
Date:
Subject: Re: [EXTERNAL] Re: Allow declaration after statement and reformat code to use it