postgresql/contrib
Tomas Vondra 3fccbd94cb Handle ENOENT status when querying NUMA node
We've assumed that touching the memory is sufficient for a page to be
located on one of the NUMA nodes. But a page may be moved to a swap
after we touch it, due to memory pressure.

We touch the memory before querying the status, but there is no
guarantee it won't be moved to the swap in the meantime. The touching
happens only on the first call, so later calls are more likely to be
affected. And the batching increases the window too.

It's up to the kernel if/when pages get moved to swap. We have to accept
ENOENT (-2) as a valid result, and handle it without failing. This patch
simply treats it as an unknown node, and returns NULL in the two
affected views (pg_shmem_allocations_numa and pg_buffercache_numa).

Hugepages cannot be swapped out, so this affects only regular pages.

Reported by Christoph Berg, investigation and fix by me. Backpatch to
18, where the two views were introduced.

Reported-by: Christoph Berg <myon@debian.org>
Discussion: 18
Backpatch-through: https://postgr.es/m/aTq5Gt_n-oS_QSpL@msg.df7cb.de
2026-01-27 00:21:40 +01:00
..
amcheck amcheck: Fix snapshot usage in bt_index_parent_check 2026-01-21 18:55:43 +01:00
auth_delay Update copyright for 2026 2026-01-01 13:24:10 -05:00
auto_explain instrumentation: Keep time fields as instrtime, convert in callers 2026-01-09 13:38:00 -05:00
basebackup_to_shell Update copyright for 2026 2026-01-01 13:24:10 -05:00
basic_archive Update copyright for 2026 2026-01-01 13:24:10 -05:00
bloom Move instrumentation-related structs to instrument_node.h 2026-01-12 16:59:28 +01:00
bool_plperl Update copyright for 2026 2026-01-01 13:24:10 -05:00
btree_gin Update copyright for 2026 2026-01-01 13:24:10 -05:00
btree_gist Mark commented out code as unused 2026-01-22 12:44:07 +01:00
citext Update copyright for 2026 2026-01-01 13:24:10 -05:00
cube Mark commented out code as unused 2026-01-22 12:44:07 +01:00
dblink Update copyright for 2026 2026-01-01 13:24:10 -05:00
dict_int Update copyright for 2026 2026-01-01 13:24:10 -05:00
dict_xsyn Update copyright for 2026 2026-01-01 13:24:10 -05:00
earthdistance Update copyright for 2026 2026-01-01 13:24:10 -05:00
file_fdw Fix bogus ctid requirement for dummy-root partitioned targets 2026-01-23 10:23:30 +09:00
fuzzystrmatch fuzzystrmatch: use pg_ascii_toupper(). 2026-01-12 08:54:04 -08:00
hstore Mark commented out code as unused 2026-01-22 12:44:07 +01:00
hstore_plperl Update copyright for 2026 2026-01-01 13:24:10 -05:00
hstore_plpython Update copyright for 2026 2026-01-01 13:24:10 -05:00
intagg Update copyright for 2026 2026-01-01 13:24:10 -05:00
intarray Fix accidentally cast away qualifiers 2026-01-26 16:02:31 +01:00
isn Update copyright for 2026 2026-01-01 13:24:10 -05:00
jsonb_plperl Update copyright for 2026 2026-01-01 13:24:10 -05:00
jsonb_plpython Update copyright for 2026 2026-01-01 13:24:10 -05:00
lo Update copyright for 2026 2026-01-01 13:24:10 -05:00
ltree Mark commented out code as unused 2026-01-22 12:44:07 +01:00
ltree_plpython Update copyright for 2026 2026-01-01 13:24:10 -05:00
oid2name Update copyright for 2026 2026-01-01 13:24:10 -05:00
pageinspect Fix accidentally cast away qualifiers 2026-01-26 16:02:31 +01:00
passwordcheck Update copyright for 2026 2026-01-01 13:24:10 -05:00
pg_buffercache Handle ENOENT status when querying NUMA node 2026-01-27 00:21:40 +01:00
pg_freespacemap Update copyright for 2026 2026-01-01 13:24:10 -05:00
pg_logicalinspect Update copyright for 2026 2026-01-01 13:24:10 -05:00
pg_overexplain Update copyright for 2026 2026-01-01 13:24:10 -05:00
pg_prewarm bufmgr: Change BufferDesc.state to be a 64-bit atomic 2026-01-15 14:20:41 -05:00
pg_stat_statements pg_stat_statements: Fix test instability with cache-clobbering builds 2026-01-25 19:01:23 +09:00
pg_surgery Update copyright for 2026 2026-01-01 13:24:10 -05:00
pg_trgm Mark commented out code as unused 2026-01-22 12:44:07 +01:00
pg_visibility Combine visibilitymap_set() cases in lazy_scan_prune() 2026-01-26 16:03:32 -05:00
pg_walinspect Update copyright for 2026 2026-01-01 13:24:10 -05:00
pgcrypto Update copyright for 2026 2026-01-01 13:24:10 -05:00
pgrowlocks Update copyright for 2026 2026-01-01 13:24:10 -05:00
pgstattuple Use relation_close() more consistently in contrib/ 2026-01-06 16:17:59 +09:00
postgres_fdw Update copyright for 2026 2026-01-01 13:24:10 -05:00
seg Mark commented out code as unused 2026-01-22 12:44:07 +01:00
sepgsql Update copyright for 2026 2026-01-01 13:24:10 -05:00
spi Update copyright for 2026 2026-01-01 13:24:10 -05:00
sslinfo Update copyright for 2026 2026-01-01 13:24:10 -05:00
start-scripts Remove gratuitous references to postmaster program 2023-01-26 10:48:32 +01:00
tablefunc Update copyright for 2026 2026-01-01 13:24:10 -05:00
tcn Update copyright for 2026 2026-01-01 13:24:10 -05:00
test_decoding Force standard_conforming_strings to always be ON. 2026-01-21 15:08:38 -05:00
tsm_system_rows Update copyright for 2026 2026-01-01 13:24:10 -05:00
tsm_system_time Update copyright for 2026 2026-01-01 13:24:10 -05:00
unaccent Update copyright for 2026 2026-01-01 13:24:10 -05:00
uuid-ossp Fix accidentally cast away qualifiers 2026-01-26 16:02:31 +01:00
vacuumlo Update copyright for 2026 2026-01-01 13:24:10 -05:00
xml2 Update copyright for 2026 2026-01-01 13:24:10 -05:00
contrib-global.mk Respect TEMP_CONFIG when pg_regress_check and friends are called 2016-02-27 12:28:21 -05:00
Makefile pg_overexplain: Additional EXPLAIN options for debugging. 2025-03-26 13:52:21 -04:00
meson.build Update copyright for 2026 2026-01-01 13:24:10 -05:00
README Rename 'gmake' to 'make' in docs and recommended commands 2014-02-12 17:29:19 -05:00

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.