Provided by: pgbouncer_1.4.2-2build1_amd64 bug

NAME

       pgbouncer - Lightweight connection pooler for PostgreSQL.

SYNOPSIS

       pgbouncer [-d][-R][-v][-u user] <pgbouncer.ini>
       pgbouncer -V|-h

       On Windows computers, the options are:

       pgbouncer.exe [-v][-u user] <pgbouncer.ini>
       pgbouncer.exe -V|-h

       Additional options for setting up a Windows service:

       pgbouncer.exe -regservice   <pgbouncer.ini>
       pgbouncer.exe -unregservice <pgbouncer.ini>

DESCRIPTION

       pgbouncer is a PostgreSQL connection pooler. Any target application can be connected to
       pgbouncer as if it were a PostgreSQL server, and pgbouncer will create a connection to the
       actual server, or it will reuse one of its existing connections.

       The aim of pgbouncer is to lower the performance impact of opening new connections to
       PostgreSQL.

       In order not to compromise transaction semantics for connection pooling, pgbouncer
       supports several types of pooling when rotating connections:

       Session pooling
           Most polite method. When client connects, a server connection will be assigned to it
           for the whole duration the client stays connected. When the client disconnects, the
           server connection will be put back into the pool. This is the default method.

       Transaction pooling
           A server connection is assigned to client only during a transaction. When PgBouncer
           notices that transaction is over, the server connection will be put back into the
           pool.

       Statement pooling
           Most aggressive method. The server connection will be put back into pool immediately
           after a query completes. Multi-statement transactions are disallowed in this mode as
           they would break.

       The administration interface of pgbouncer consists of some new SHOW commands available
       when connected to a special virtual database pgbouncer.

QUICK-START

       Basic setup and usage as following.

        1. Create a pgbouncer.ini file. Details in pgbouncer(5). Simple example:

               [databases]
               template1 = host=127.0.0.1 port=5432 dbname=template1

               [pgbouncer]
               listen_port = 6543
               listen_addr = 127.0.0.1
               auth_type = md5
               auth_file = users.txt
               logfile = pgbouncer.log
               pidfile = pgbouncer.pid
               admin_users = someuser

        2. Create a users.txt file:

               "someuser" "same_password_as_in_server"

        3. Launch pgbouncer:

               $ pgbouncer -d pgbouncer.ini

        4. Have your application (or the psql client) connect to pgbouncer instead of directly to
           PostgreSQL server.

               $ psql -p 6543 -U someuser template1

        5. Manage pgbouncer by connecting to the special administration database pgbouncer and
           issuing show help; to begin:

               $ psql -p 6543 -U someuser pgbouncer
               pgbouncer=# show help;
               NOTICE:  Console usage
               DETAIL:
                 SHOW [HELP|CONFIG|DATABASES|FDS|POOLS|CLIENTS|SERVERS|SOCKETS|LISTS|VERSION]
                 SET key = arg
                 RELOAD
                 PAUSE
                 SUSPEND
                 RESUME
                 SHUTDOWN

        6. If you made changes to the pgbouncer.ini file, you can reload it with:

               pgbouncer=# RELOAD;

COMMAND LINE SWITCHES

       -d
           Run in background. Without it the process will run in foreground. Note: Does not work
           on Windows, pgbouncer need to run as service there.

       -R
           Do an online restart. That means connecting to the running process, loading the open
           sockets from it, and then using them. If there is no active process, boot normally.
           Note: Works only if OS supports Unix sockets and the unix_socket_dir is not disabled
           in config. Does not work on Windows machines.

       -u user
           Switch to the given user on startup.

       -v
           Increase verbosity. Can be used multiple times.

       -q
           Be quiet - do not log to stdout. Note this does not affect logging verbosity, only
           that stdout is not to be used. For use in init.d scripts.

       -V
           Show version.

       -h
           Show short help.

       -regservice
           Win32: Register pgbouncer to run as Windows service. The service_name config parameter
           value is used as name to register under.

       -unregservice
           Win32: Unregister Windows service.

ADMIN CONSOLE

       The console is available by connecting as normal to the database pgbouncer

           $ psql -p 6543 pgbouncer

       Only users listed in configuration parameters admin_users or stats_users are allowed to
       login to the console. (Except when auth_mode=any, then any user is allowed in as an
       admin.)

       Additionally, the username pgbouncer is allowed to log in without password, if the login
       comes via Unix socket and the client has same Unix user uid as the running process.

   SHOW COMMANDS
       The SHOW commands output information. Each command is described below.

       SHOW STATS;
           Shows statistics.

           database
               Statistics are presented per database.

           total_requests
               Total number of SQL requests pooled by pgbouncer.

           total_received
               Total volume in bytes of network traffic received by pgbouncer.

           total_sent
               Total volume in bytes of network traffic sent by pgbouncer.

           total_query_time
               Total number of microseconds spent by pgbouncer when actively connected to
               PostgreSQL.

           avg_req
               Average requests per second in last stat period.

           avg_recv
               Average received (from clients) bytes per second.

           avg_sent
               Average sent (to clients) bytes per second.

           avg_query
               Average query duration in microseconds.

       SHOW SERVERS;
           type
               S, for server.

           user
               Username pgbouncer uses to connect to server.

           database
               Database name.

           state
               State of the pgbouncer server connection, one of active, used or idle.

           addr
               IP address of PostgreSQL server.

           port
               Port of PostgreSQL server.

           local_addr
               Connection start address on local machine.

           local_port
               Connection start port on local machine.

           connect_time
               When the connection was made.

           request_time
               When last request was issued.

           ptr
               Address of internal object for this connection. Used as unique ID.

           link
               Address of client connection the server is paired with.

       SHOW CLIENTS;
           type
               C, for client.

           user
               Client connected user.

           database
               Database name.

           state
               State of the client connection, one of active, used, waiting or idle.

           addr
               IP address of client.

           port
               Port client is connected to.

           local_addr
               Connection end address on local machine.

           local_port
               Connection end port on local machine.

           connect_time
               Timestamp of connect time.

           request_time
               Timestamp of latest client request.

           ptr
               Address of internal object for this connection. Used as unique ID.

           link
               Address of server connection the client is paired with.

       SHOW POOLS;
           A new pool entry is made for each couple of (database, user).

           database
               Database name.

           user
               Username.

           cl_active
               Count of currently active client connections.

           cl_waiting
               Count of currently waiting client connections.

           sv_active
               Count of currently active server connections.

           sv_idle
               Count of currently idle server connections.

           sv_used
               Count of currently used server connections.

           sv_tested
               Count of currently tested server connections.

           sv_login
               Count of server connections currently logged in to PostgreSQL.

           maxwait
               How long the first (oldest) client in queue has waited, in seconds. If this starts
               increasing, then the current pool of servers does not handle requests quick
               enough. Reason may be either overloaded server or just too small of a pool_size
               setting.

       SHOW LISTS;
           Show following internal information, in columns (not rows):

           databases
               Count of databases.

           users
               Count of users.

           pools
               Count of pools.

           free_clients
               Count of free clients.

           used_clients
               Count of used clients.

           login_clients
               Count of clients in login state.

           free_servers
               Count of free servers.

           used_servers
               Count of used servers.

       SHOW USERS;
           Shows one line per user, under the name column name.

       SHOW DATABASES;
           name
               Name of configured database entry.

           host
               Host pgbouncer connects to.

           port
               Port pgbouncer connects to.

           database
               Actual database name pgbouncer connects to.

           force_user
               When user is part of the connection string, the connection between pgbouncer and
               PostgreSQL is forced to the given user, whatever the client user.

           pool_size
               Maximum number of server connections.

       SHOW FDS;
           Shows list of fds in use. When the connected user has username "pgbouncer", connects
           through Unix socket and has same UID as running process, the actual fds are passed
           over the connection. This mechanism is used to do an online restart. Note: This does
           not work on Windows machines.

           fd
               File descriptor numeric value.

           task
               One of pooler, client or server.

           user
               User of the connection using the FD.

           database
               Database of the connection using the FD.

           addr
               IP address of the connection using the FD, unix if a unix socket is used.

           port
               Port used by the connection using the FD.

           cancel
               Cancel key for this connection.

           link
               fd for corresponding server/client. NULL if idle.

       SHOW CONFIG;
           Show the current configuration settings, one per row, with following columns:

           key
               Configuration variable name

           value
               Configuration value

           changeable
               Either yes or no, shows if the variable can be changed while running. If no, the
               variable can be changed only boot-time.

   PROCESS CONTROLLING COMMANDS
       PAUSE;
           PgBouncer tries to disconnect from all servers, first waiting for all queries to
           complete. The command will not return before all queries are finished. To be used at
           the time of database restart.

       SUSPEND;
           All socket buffers are flushed and PgBouncer stops listening for data on them. The
           command will not return before all buffers are empty. To be used at the time of
           PgBouncer online reboot.

       RESUME;
           Resume work from previous PAUSE or SUSPEND command.

       SHUTDOWN;
           The PgBouncer process will exit.

       RELOAD;
           The PgBouncer process will reload its configuration file and update changeable
           settings.

   SIGNALS
       SIGHUP
           Reload config. Same as issuing command RELOAD; on console.

       SIGINT
           Safe shutdown. Same as issuing PAUSE; and SHUTDOWN; on console.

       SIGTERM
           Immediate shutdown. Same as issuing SHUTDOWN; on console.

   LIBEVENT SETTINGS
       From libevent docs:

           It is possible to disable support for epoll, kqueue, devpoll, poll
           or select by setting the environment variable EVENT_NOEPOLL,
           EVENT_NOKQUEUE, EVENT_NODEVPOLL, EVENT_NOPOLL or EVENT_NOSELECT,
           respectively.

           By setting the environment variable EVENT_SHOW_METHOD, libevent
           displays the kernel notification method that it uses.

SEE ALSO

       pgbouncer(5) - manpage of configuration settings descriptions.

       http://wiki.postgresql.org/wiki/PgBouncer

                                            12/03/2011                               PGBOUNCER(1)