File Structure

These parameters are related to pigsty file structure

• pg_dbsu_home：Postgres DBSU home directory, /var/lib/pgsql by default
• pg_bin_dir：Postgres binary directory, /usr/pgsql/bin/ by default.
• pg_data: Postgres data directory, /pg/data by default.
• pg_fs_main: Postgres main disk mount point, /export by default.
• pg_fs_bkup: Postgres backup disk mount point /var/backups by default

Overview

#------------------------------------------------------------------------------
# Create Directory
#------------------------------------------------------------------------------
# this assumes that
#   /pg is shortcut for postgres home
#   {{ pg_fs_main }} contains the main data             (MUST ALREADY MOUNTED)
#   {{ pg_fs_bkup }} contains archive and backup data   (MUST ALREADY MOUNTED)
#   cluster-version is the default parent folder for pgdata (e.g pg-test-12)
#------------------------------------------------------------------------------
# default variable:
#     pg_fs_main = /export           fast ssd
#     pg_fs_bkup = /var/backups      cheap hdd
#
#     /pg      -> /export/postgres/pg-test-12
#     /pg/data -> /export/postgres/pg-test-12/data
#------------------------------------------------------------------------------
- name: Create postgresql directories
  tags: pg_dir
  become: yes
  block:
    - name: Make sure main and backup dir exists
      file: path={{ item }} state=directory owner=root mode=0777
      with_items:
        - "{{ pg_fs_main }}"
        - "{{ pg_fs_bkup }}"

    # pg_cluster_dir:    "{{ pg_fs_main }}/postgres/{{ pg_cluster }}-{{ pg_version }}"
    - name: Create postgres directory structure
      file: path={{ item }} state=directory owner={{ pg_dbsu }} group=postgres mode=0700
      with_items:
        - "{{ pg_fs_main }}/postgres"
        - "{{ pg_cluster_dir }}"
        - "{{ pg_cluster_dir }}/bin"
        - "{{ pg_cluster_dir }}/log"
        - "{{ pg_cluster_dir }}/tmp"
        - "{{ pg_cluster_dir }}/conf"
        - "{{ pg_cluster_dir }}/data"
        - "{{ pg_cluster_dir }}/meta"
        - "{{ pg_cluster_dir }}/stat"
        - "{{ pg_cluster_dir }}/change"
        - "{{ pg_backup_dir }}/postgres"
        - "{{ pg_backup_dir }}/arcwal"
        - "{{ pg_backup_dir }}/backup"
        - "{{ pg_backup_dir }}/remote"

PG二进制目录结构

在RedHat/CentOS上，默认的Postgres发行版安装位置为

/usr/pgsql-${pg_version}/

安装剧本会自动创建指向当前安装版本的软连接，例如，如果安装了13版本的Postgres，则有：

/usr/pgsql -> /usr/pgsql-13

因此，默认的pg_bin_dir为/usr/pgsql/bin/，该路径会在/etc/profile.d/pgsql.sh中添加至所有用户的PATH环境变量中。

PG数据目录结构

Pigsty假设用于部署数据库实例的单个节点上至少有一块主数据盘（pg_fs_main），以及一块可选的备份数据盘（pg_fs_bkup）。通常主数据盘是高性能SSD，而备份盘是大容量廉价HDD。

#------------------------------------------------------------------------------
# Create Directory
#------------------------------------------------------------------------------
# this assumes that
#   /pg is shortcut for postgres home
#   {{ pg_fs_main }} contains the main data             (MUST ALREADY MOUNTED)
#   {{ pg_fs_bkup }} contains archive and backup data   (MAYBE ALREADY MOUNTED)
#   {{ pg_cluster }}-{{ pg_version }} is the default parent folder 
#    for pgdata (e.g pg-test-12)
#------------------------------------------------------------------------------
# default variable:
#     pg_fs_main = /export           fast ssd
#     pg_fs_bkup = /var/backups      cheap hdd
#
#     /pg      -> /export/postgres/pg-test-12
#     /pg/data -> /export/postgres/pg-test-12/data

Database Cluster Directories

# basic
{{ pg_fs_main }}     /export                      # contains all business data (pg,consul,etc..)
{{ pg_dir_main }}    /export/postgres             # contains postgres main data
{{ pg_cluster_dir }} /export/postgres/pg-test-13  # contains cluster `pg-test` data (of version 13)
                     /export/postgres/pg-test-13/bin            # binary scripts
                     /export/postgres/pg-test-13/log            # misc logs
                     /export/postgres/pg-test-13/tmp            # tmp, sql files, records
                     /export/postgres/pg-test-13/conf           # configurations
                     /export/postgres/pg-test-13/data           # main data directory
                     /export/postgres/pg-test-13/meta           # identity information
                     /export/postgres/pg-test-13/stat           # stats information
                     /export/postgres/pg-test-13/change         # changing records

{{ pg_fs_bkup }}     /var/backups                      # contains all backup data (pg,consul,etc..)
{{ pg_dir_bkup }}    /var/backups/postgres             # contains postgres backup data
{{ pg_backup_dir }}  /var/backups/postgres/pg-test-13  # contains cluster `pg-test` backup (of version 13)
                     /var/backups/postgres/pg-test-13/backup   # base backup
                     /var/backups/postgres/pg-test-13/arcwal   # WAL archive
                     /var/backups/postgres/pg-test-13/remote   # mount NFS/S3 remote resources here

# links
/pg             -> /export/postgres/pg-test-12               # pg root link
/pg/data        -> /export/postgres/pg-test-12/data          # real data dir
/pg/backup      -> /var/backups/postgres/pg-test-13/backup   # base backup
/pg/arcwal      -> /var/backups/postgres/pg-test-13/arcwal   # WAL archive
/pg/remote      -> /var/backups/postgres/pg-test-13/remote   # mount NFS/S3 remote resources here

Pgbouncer配置文件结构

Pgbouncer使用Postgres用户运行，配置文件位于/etc/pgbouncer。配置文件包括：

• pgbouncer.ini，主配置文件
• userlist.txt：列出连接池中的用户
• pgb_hba.conf：列出连接池用户的访问权限
• database.txt：列出连接池中的数据库