Re: recovering from "found xmin ... from before relfrozenxid ..."

Robert Haas <robertmhaas@gmail.com>

From: Robert Haas <robertmhaas@gmail.com>
To: Thomas Munro <thomas.munro@gmail.com>
Cc: "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2020-07-29T13:36:31Z
Lists: pgsql-hackers
On Wed, Jul 29, 2020 at 3:23 AM Thomas Munro <thomas.munro@gmail.com> wrote:
> On Tue, Jul 14, 2020 at 9:12 AM Robert Haas <robertmhaas@gmail.com> wrote:
> > A number of EDB customers have had this error crop on their tables for
> > reasons that we have usually not been able to determine. In many
>
> <long-shot>Do you happen to know if they ever used the
> snapshot-too-old feature?</long-shot>

I don't have any reason to believe that they did. Why?

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



Commits

  1. Fix wrong data table horizon computation during backend startup.

  2. Centralize horizon determination for temp tables, fixing bug due to skew.

  3. pg_surgery: Try to stabilize regression tests.

  4. New contrib module, pg_surgery, with heap surgery functions.

  5. Set cutoff xmin more aggressively when vacuuming a temporary table.

  6. snapshot scalability: Don't compute global horizons while building snapshots.

  7. Introduce vacuum errcontext to display additional information.