Horton

Re: pg_amcheck contrib application

Peter Geoghegan <pg@bowt.ie>

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From: Peter Geoghegan <pg@bowt.ie>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Robert Haas <robertmhaas@gmail.com>, Mark Dilger <mark.dilger@enterprisedb.com>, Noah Misch <noah@leadboat.com>, Thomas Munro <thomas.munro@gmail.com>, "Andrey M. Borodin" <x4mmm@yandex-team.ru>, Stephen Frost <sfrost@snowman.net>, Michael Paquier <michael@paquier.xyz>, Amul Sul <sulamul@gmail.com>, Dilip Kumar <dilipbalaut@gmail.com>, Andres Freund <andres@anarazel.de>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2021-03-23T19:53:35Z
Lists: pgsql-hackers 
On Tue, Mar 23, 2021 at 12:44 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> > I will make this change to HEAD soon, barring objections.
>
> +1.  Not deleting the upper page seems better than the alternatives.

FWIW it might also work that way as a holdover from the old page
deletion algorithm. These days we decide exactly which pages (leaf
page plus possible internal pages) are to be deleted as a whole up
front (these are a subtree, though usually just a degenerate
single-leaf-page subtree -- internal page deletions are rare).

One of the advantages of this design is that we verify practically all
of the work involved in deleting an entire subtree up-front, inside
_bt_lock_subtree_parent(). It's clearly safe to back out of it if it
looks dicey.

--
Peter Geoghegan

Commits

  1. amcheck: Improve some confusing reports about TOAST problems.

  2. amcheck: Reword some messages and fix an alignment problem.

  3. amcheck: fix multiple problems with TOAST pointer validation

  4. amcheck: Remove duplicate XID/MXID bounds checks.

  5. amcheck: Fix verify_heapam's tuple visibility checking rules.

  6. nbtree VACUUM: Cope with buggy opclasses.

  7. Improve pg_amcheck's TAP test 003_check.pl.

  8. Fix a confusing amcheck corruption message.

  9. Doc: add note about how to run the pg_amcheck regression tests.

  10. In pg_amcheck tests, don't depend on perl's Q/q pack code.

  11. pg_amcheck: Keep trying to fix the tests.

  12. pg_amcheck: Try to fix still more test failures.

  13. Try to avoid apparent platform-dependency in IPC::Run

  14. Fix portability issues in pg_amcheck's 004_verify_heapam.pl.

  15. Try to fix compiler warnings.

  16. Add pg_amcheck, a CLI for contrib/amcheck.

  17. Refactor and generalize the ParallelSlot machinery.

  18. Remove old-style VACUUM FULL (which was known for a little while as