SHOW POOL_POOLS sends back a list of pools handled by Pgpool-II
It has 20 columns:
pool_pid is the PID of the displayed Pgpool-II process.
start_time is the timestamp of when this process was launched.
If child_life_time is set not 0, the time before process restarting is displayed.
client_connection_count counts the number of times this process has been used by clients.
pool_id is the pool identifier (should be between 0 and max_pool - 1)
backend_id is the backend identifier (should be between 0 and the number of configured backends minus one)
database is the database name for this process's pool id connection.
username is the user name for this process's pool id connection.
backend_connection_time is the creation time and date of the connection.
client_connection_time is the date when a client last used this connection.
client_disconnection_time is the date when a client last disconnected from this connection.
client_idle_duration is the time (sec) that a client is in idle.
If client_idle_limit is set not 0, the time before client disconnected is displayed.
majorversion and minorversion are the protocol version numbers used in this connection.
pool_counter counts the number of times this pool of connections (process) has been used by clients.
pool_backendpid is the PID of the PostgreSQL process.
pool_connected is true (1) if a frontend is currently using this backend.
status is current status of this process. Possible values are:
Execute command: Executing a command.
Idle: The process is waiting for a new client command.
Idle in transaction: The process is waiting for a new client command in a transaction.
Wait for connection: The process is waiting for a new client connection.
load_balance_node is true (1) if a frontend is currently using this backend and the backend is load balance node.
client_host is client's host name or IP address.
client_port is client's port number.
statement is the SQL statement last executed.
It'll always return num_init_children * max_pool * number_of_backends lines. Here is an example session:
test=# show pool_pools;
pool_pid | start_time | client_connection_count | pool_id | backend_id | database | username | backend_connection_time | client_connection_time | client_disconnection_time | client_idle_duration | majorversion | minorversion | pool_counter | pool_backendpid | pool_connected | status | load_balance_node | client_host | client_port | statement
----------+------------------------------------------------------+-------------------------+---------+------------+----------+----------+-------------------------+------------------------+---------------------------+----------------------+--------------+--------------+--------------+-----------------+----------------+---------------------+-------------------+---------------+-------------+-------------
[snip]
1336537 | 2025-06-24 10:53:35 | 0 | 0 | 0 | test | t-ishii | 2025-06-24 10:55:58 | 2025-06-24 10:55:59 | | 0 | 3 | 0 | 1 | 1336703 | 1 | Idle | 0 | 192.168.10.11 | 39216 |
1336537 | 2025-06-24 10:53:35 | 0 | 0 | 1 | test | t-ishii | 2025-06-24 10:55:58 | 2025-06-24 10:55:59 | | 0 | 3 | 0 | 1 | 1336704 | 1 | Idle | 1 | 192.168.10.11 | 39216 | select 1;
1336537 | 2025-06-24 10:53:35 | 0 | 1 | 0 | | | | | | 0 | 0 | 0 | 0 | 0 | 0 | Idle | 0 | 192.168.10.11 | 39216 |
1336537 | 2025-06-24 10:53:35 | 0 | 1 | 1 | | | | | | 0 | 0 | 0 | 0 | 0 | 0 | Idle | 0 | 192.168.10.11 | 39216 | select 1;
1336537 | 2025-06-24 10:53:35 | 0 | 2 | 0 | | | | | | 0 | 0 | 0 | 0 | 0 | 0 | Idle | 0 | 192.168.10.11 | 39216 |
1336537 | 2025-06-24 10:53:35 | 0 | 2 | 1 | | | | | | 0 | 0 | 0 | 0 | 0 | 0 | Idle | 0 | 192.168.10.11 | 39216 | select 1;
1336537 | 2025-06-24 10:53:35 | 0 | 3 | 0 | | | | | | 0 | 0 | 0 | 0 | 0 | 0 | Idle | 0 | 192.168.10.11 | 39216 |
1336537 | 2025-06-24 10:53:35 | 0 | 3 | 1 | | | | | | 0 | 0 | 0 | 0 | 0 | 0 | Idle | 0 | 192.168.10.11 | 39216 | select 1;
[snip]
1336544 | 2025-06-24 10:53:35 (0:23 before process restarting) | 1 | 0 | 0 | test | t-ishii | 2025-06-24 10:53:42 | 2025-06-24 10:53:42 | 2025-06-24 10:55:37 | 0 | 3 | 0 | 1 | 1336573 | 0 | Wait for connection | 0 | 192.168.10.11 | 39162 | DISCARD ALL
1336544 | 2025-06-24 10:53:35 (0:23 before process restarting) | 1 | 0 | 1 | test | t-ishii | 2025-06-24 10:53:42 | 2025-06-24 10:53:42 | 2025-06-24 10:55:37 | 0 | 3 | 0 | 1 | 1336574 | 0 | Wait for connection | 0 | 192.168.10.11 | 39162 |
1336544 | 2025-06-24 10:53:35 (0:23 before process restarting) | 1 | 1 | 0 | | | | | | 0 | 0 | 0 | 0 | 0 | 0 | Wait for connection | 0 | 192.168.10.11 | 39162 | DISCARD ALL
1336544 | 2025-06-24 10:53:35 (0:23 before process restarting) | 1 | 1 | 1 | | | | | | 0 | 0 | 0 | 0 | 0 | 0 | Wait for connection | 0 | 192.168.10.11 | 39162 |
1336544 | 2025-06-24 10:53:35 (0:23 before process restarting) | 1 | 2 | 0 | | | | | | 0 | 0 | 0 | 0 | 0 | 0 | Wait for connection | 0 | 192.168.10.11 | 39162 | DISCARD ALL
1336544 | 2025-06-24 10:53:35 (0:23 before process restarting) | 1 | 2 | 1 | | | | | | 0 | 0 | 0 | 0 | 0 | 0 | Wait for connection | 0 | 192.168.10.11 | 39162 |
1336544 | 2025-06-24 10:53:35 (0:23 before process restarting) | 1 | 3 | 0 | | | | | | 0 | 0 | 0 | 0 | 0 | 0 | Wait for connection | 0 | 192.168.10.11 | 39162 | DISCARD ALL
1336544 | 2025-06-24 10:53:35 (0:23 before process restarting) | 1 | 3 | 1 | | | | | | 0 | 0 | 0 | 0 | 0 | 0 | Wait for connection | 0 | 192.168.10.11 | 39162 |
[snip]
(256 rows)