The documentation at https://www.postgresql.org/docs/current/static/storage-vm.html says that the visibility map "keeps track of which pages contain only unfrozen tuples".
This is wrong; it keeps track of all-frozen pages not all-unfrozen. Trivial patch attached. -- Vik Fearing +33 6 46 75 15 36 http://2ndQuadrant.fr PostgreSQL : Expertise, Formation et Support
diff --git a/doc/src/sgml/storage.sgml b/doc/src/sgml/storage.sgml index a156693ec8..aed2cf8bca 100644 --- a/doc/src/sgml/storage.sgml +++ b/doc/src/sgml/storage.sgml @@ -630,7 +630,7 @@ can be used to examine the information stored in free space maps. Each heap relation has a Visibility Map (VM) to keep track of which pages contain only tuples that are known to be visible to all active transactions; it also keeps track of which pages contain -only unfrozen tuples. It's stored +only frozen tuples. It's stored alongside the main relation data in a separate relation fork, named after the filenode number of the relation, plus a <literal>_vm</> suffix. For example, if the filenode of a relation is 12345, the VM is stored in a file called
-- Sent via pgsql-docs mailing list (pgsql-docs@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-docs
