postgres/contrib
Amit Kapila 4909b38af0 Fix data loss in logical replication.
Data loss can happen when the DDLs like ALTER PUBLICATION ... ADD TABLE ...
or ALTER TYPE ...  that don't take a strong lock on table happens
concurrently to DMLs on the tables involved in the DDL. This happens
because logical decoding doesn't distribute invalidations to concurrent
transactions and those transactions use stale cache data to decode the
changes. The problem becomes bigger because we keep using the stale cache
even after those in-progress transactions are finished and skip the
changes required to be sent to the client.

This commit fixes the issue by distributing invalidation messages from
catalog-modifying transactions to all concurrent in-progress transactions.
This allows the necessary rebuild of the catalog cache when decoding new
changes after concurrent DDL.

We observed performance regression primarily during frequent execution of
*publication DDL* statements that modify the published tables. The
regression is minor or nearly nonexistent for DDLs that do not affect the
published tables or occur infrequently, making this a worthwhile cost to
resolve a longstanding data loss issue.

An alternative approach considered was to take a strong lock on each
affected table during publication modification. However, this would only
address issues related to publication DDLs (but not the ALTER TYPE ...)
and require locking every relation in the database for publications
created as FOR ALL TABLES, which is impractical.

The bug exists in all supported branches, but we are backpatching till 14.
The fix for 13 requires somewhat bigger changes than this fix, so the fix
for that branch is still under discussion.

Reported-by: hubert depesz lubaczewski <depesz@depesz.com>
Reported-by: Tomas Vondra <tomas.vondra@enterprisedb.com>
Author: Shlok Kyal <shlok.kyal.oss@gmail.com>
Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Tested-by: Benoit Lobréau <benoit.lobreau@dalibo.com>
Backpatch-through: 14
Discussion: https://postgr.es/m/de52b282-1166-1180-45a2-8d8917ca74c6@enterprisedb.com
Discussion: https://postgr.es/m/CAD21AoAenVqiMjpN-PvGHL1N9DWnHSq673bfgr6phmBUzx=kLQ@mail.gmail.com
2025-04-10 13:14:40 +05:30
..
amcheck Remove misleading read stream asserts in a few users 2025-04-03 18:22:37 -04:00
auth_delay Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
auto_explain Introduce PG_MODULE_MAGIC_EXT macro. 2025-03-26 11:06:12 -04:00
basebackup_to_shell Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
basic_archive Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
bloom Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
bool_plperl Fix erroneous construction of functions' dependencies on transforms. 2025-04-07 13:31:37 -04:00
btree_gin Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
btree_gist Add support for sorted gist index builds to btree_gist 2025-04-03 13:46:35 +03:00
citext Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
cube Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
dblink Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
dict_int Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
dict_xsyn Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
earthdistance Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
file_fdw Use PRI?64 instead of "ll?" in format strings (continued). 2025-03-29 10:43:57 +01:00
fuzzystrmatch Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
hstore Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
hstore_plperl Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
hstore_plpython Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
intagg Update copyright for 2025 2025-01-01 11:21:55 -05:00
intarray Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
isn Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
jsonb_plperl Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
jsonb_plpython Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
lo Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
ltree Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
ltree_plpython Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
oid2name Update copyright for 2025 2025-01-01 11:21:55 -05:00
pageinspect Use PRI?64 instead of "ll?" in format strings (continued). 2025-03-29 10:43:57 +01:00
passwordcheck Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
pg_buffercache Cleanup of pg_numa.c 2025-04-09 21:50:17 +02:00
pg_freespacemap Prevent assertion failure in contrib/pg_freespacemap. 2025-03-27 13:20:23 -04:00
pg_logicalinspect Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
pg_overexplain pg_overexplain: Use PG_MODULE_MAGIC_EXT. 2025-03-28 09:16:29 -04:00
pg_prewarm Use streaming read I/O in autoprewarm 2025-04-04 15:28:54 -04:00
pg_stat_statements Remove the query_id_squash_values GUC 2025-03-27 13:33:37 +01:00
pg_surgery Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
pg_trgm Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
pg_visibility read_stream: Introduce and use optional batchmode support 2025-03-30 18:36:41 -04:00
pg_walinspect Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
pgcrypto Fix incorrect format placeholder 2025-04-08 19:12:03 +02:00
pgrowlocks Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
pgstattuple Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
postgres_fdw Speedup child EquivalenceMember lookup in planner 2025-04-08 18:09:57 +12:00
seg Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
sepgsql Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
spi Move contrib/spi testing from core regression tests to contrib/spi. 2025-04-08 19:12:03 -04:00
sslinfo Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
start-scripts Remove gratuitous references to postmaster program 2023-01-26 10:48:32 +01:00
tablefunc Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
tcn Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
test_decoding Fix data loss in logical replication. 2025-04-10 13:14:40 +05:30
tsm_system_rows Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
tsm_system_time Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
unaccent Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
uuid-ossp Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
vacuumlo Update copyright for 2025 2025-01-01 11:21:55 -05:00
xml2 Use PG_MODULE_MAGIC_EXT in our installable shared libraries. 2025-03-26 11:11:02 -04:00
contrib-global.mk
Makefile pg_overexplain: Additional EXPLAIN options for debugging. 2025-03-26 13:52:21 -04:00
meson.build pg_overexplain: Additional EXPLAIN options for debugging. 2025-03-26 13:52:21 -04:00
README

The PostgreSQL contrib tree
---------------------------

This subtree contains porting tools, analysis utilities, and plug-in
features that are not part of the core PostgreSQL system, mainly
because they address a limited audience or are too experimental to be
part of the main source tree.  This does not preclude their
usefulness.

User documentation for each module appears in the main SGML
documentation.

When building from the source distribution, these modules are not
built automatically, unless you build the "world" target.  You can
also build and install them all by running "make all" and "make
install" in this directory; or to build and install just one selected
module, do the same in that module's subdirectory.

Some directories supply new user-defined functions, operators, or
types.  To make use of one of these modules, after you have installed
the code you need to register the new SQL objects in the database
system by executing a CREATE EXTENSION command.  In a fresh database,
you can simply do

    CREATE EXTENSION module_name;

See the PostgreSQL documentation for more information about this
procedure.