Re: New vacuum option to do only freezing - Mailing list pgsql-hackers

From Tom Lane
Subject Re: New vacuum option to do only freezing
Date
Msg-id 28991.1555376836@sss.pgh.pa.us
Whole thread Raw
In response to Re: New vacuum option to do only freezing  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: New vacuum option to do only freezing
Re: New vacuum option to do only freezing
List pgsql-hackers
Robert Haas <robertmhaas@gmail.com> writes:
> On Mon, Apr 15, 2019 at 3:47 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> No.  I'm thinking there should be exactly one test of index_cleanup
>> in this logic, and what it would be is along the lines of ...

> I'm not sure that's correct.  If you do that, it'll end up in the
> non-tupgone case, which might try to freeze a tuple that should've
> been removed.  Or am I confused?

If we're failing to remove it, and it's below the desired freeze
horizon, then we'd darn well better freeze it instead, no?

Since we know that the tuple only just became dead, I suspect
that the case would be unreachable in practice.  But the approach
you propose risks violating the invariant that all old tuples
will either be removed or frozen.

            regards, tom lane



pgsql-hackers by date:

Previous
From: Robert Haas
Date:
Subject: Re: finding changed blocks using WAL scanning
Next
From: "Jamison, Kirk"
Date:
Subject: RE: Speedup of relation deletes during recovery