PostgreSQL Physical Storage

base

Subdirectory containing per-database subdirectories.

global

Subdirectory containing cluster-wide tables, such as pg_database.

pg_commit_ts

Subdirectory containing transaction commit timestamp data.

pg_dynshmem

Subdirectory containing files used by the dynamic shared memory subsystem.

pg_logical

Subdirectory containing status data for logical decoding.

pg_multixact

Subdirectory containing multitransaction status data (used for shared row locks).

pg_notify

Subdirectory containing LISTEN/NOTIFY status data.

pg_replslot

Subdirectory containing replication slot data.

pg_serial

Subdirectory containing information about committed serializable transactions.

pg_snapshots

Subdirectory containing exported snapshots.

pg_stat

Subdirectory containing permanent files for the statistics subsystem.

pg_stat_tmp

Subdirectory containing temporary files for the statistics subsystem.

pg_subtrans

Subdirectory containing sub transaction status data.

pg_tblspc

Subdirectory containing symbolic links to tablespaces.

pg_twophase

Subdirectory containing state files for prepared transactions.

log or pg_log (before postgres 9.6)

File recording the log file(s) currently written to by the logging collector.

pg_wal or pg_xlog(before postgres 9.6)

Subdirectory containing WAL (Write Ahead Log) files.

pg_xact or pg_clog (before postgres 9.6)

Subdirectory containing transaction commit status data.

pg_hba.conf

A file containing client(hostname, dbname, username and password method)
authentication and authorization.

postgresql.conf

A file containing server parameters.

postgresql.auto.conf

A file used for storing configuration parameters that are set by ALTER SYSTEM.

postmaster.opts

A file recording the command-line options the server was last started with.

postmaster.pid

A lock file recording the current postmaster process ID (PID), cluster data directory path, postmaster start timestamp, port number, Unix-domain socket directory path (empty on Windows), first valid listen_address (IP address or *, or empty if not listening on TCP), and shared memory segment ID (this file is not present after server shutdown).

PG_VERSION

A file containing the major version number of PostgreSQL