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       pgbouncer - Lightweight connection pooler for PostgreSQL.


       db = ...



       Config file is in "ini" format. Section names are between " and ".
       Lines starting with ";" or "" are taken as comments and ignored. The
       characters ";" and "" are not recognized when they appear later in the


   Generic settings
           Specifies log file. Log file is kept open so after rotation kill
           -HUP or on console RELOAD; should be done. Note: On Windows
           machines, the service must be stopped and started.

           Default: not set.

           Specifies the pid file. Without a pidfile, daemonization is not

           Default: not set.

           Specifies IPv4 address, where to listen for TCP connections. You
           may also use * meaning "listen on all addresses". When not set,
           only Unix socket connections are allowed.

           Default: not set

           Which port to listen on. Applies to both TCP and Unix sockets.

           Default: 6432

           Specifies location for Unix sockets. Applies to both listening
           socket and server connections. If set to an empty string, Unix
           sockets are disabled. Note: Not supported on Windows machines.

           Default: /tmp

           If set, specifies the Unix user to change to after startup. Works
           only if PgBouncer is started as root or if user is the same as the
           current user. Note: Not supported on Windows machines.

           Default: not set

           The name of the file to load user names and passwords from. The
           file format is the same as the PostgreSQL pg_auth/pg_pwd file, so
           this setting can be pointed directly to one of those backend files.

           Default: not set.

           How to authenticate users.

           md5: Use MD5-based password check. auth_file may contain both
           MD5-encrypted or plain-text passwords. This is the default
           authentication method.

               Use crypt(3) based password check.  auth_file must contain
               plain-text passwords.

               Clear-text password is sent over wire.

               No authentication is done. Username must still exist in

               Like the trust method, but the username given is ignored.
               Requires that all databases are configured to log in as
               specific user. Additionally, the console database allows any
               user to log in as admin.

           Specifies when a server connection can be reused by other clients.

               Server is released back to pool after client disconnects.

               Server is released back to pool after transaction finishes.

               Server is released back to pool after query finishes. Long
               transactions spanning multiple statements are disallowed in
               this mode.

           Maximum number of client connections allowed. When increased then
           the file descriptor limits should also be increased. Note that
           actual number of file descriptors used is more than
           max_client_conn. Theoretical maximum used is:

               max_client_conn + (max_pool_size * total_databases * total_users)

           if each user connects under its own username to server. If a
           database user is specified in connect string (all users connect
           under same username), the theoretical maximum is:

               max_client_conn + (max_pool_size * total_databases)

           The theoretical maximum should be never reached, unless somebody
           deliberately crafts special load for it. Still, it means you should
           set the number of file descriptors to a safely high number.

           Search for ulimit in your favourite shell man page. Note: ulimit
           does not apply in a Windows environment.

           Default: 100

           How many server connections to allow per user/database pair. Can be
           overriden in the per-database configuration.

           Default: 20

           How many additional connections to allow to a pool. 0 disables.

           Default: 0 (disabled)

           If a client has not been serviced in this many seconds, pgbouncer
           enables use of additional connections from reserve pool. 0

           Default: 5

           By default, pgbouncer reuses server connections in LIFO (last-in,
           first-out) manner, so that few connections get the most load. This
           gives best performance if you have a single server serving a
           database. But if there is TCP round-robin behind a database IP,
           then it is better if pgbouncer also uses connections in that
           manner, thus achieving uniform load.

           Default: 0

           By default, PgBouncer allows only parameters it can keep track of
           in startup packets - client_encoding, datestyle, timezone and

           All others parameters will raise an error. To allow others
           parameters, they can be specified here, so that pgbouncer knows
           that they are handled by admin and it can ignore them.

           Default: empty

   Log settings
           Toggles syslog on/off As for windows environment, eventlog is used

           Default: 0

           Under what facility to send logs to syslog. Possibilities: auth,
           authpriv, daemon, user, local0-7

           Default: daemon

           Log successful logins.

           Default: 1

           Log disconnections with reasons.

           Default: 1

           Log error messages pooler sends to clients.

           Default: 1

   Console access control
           Comma-separated list of database users that are allowed to connect
           and run all commands on console. Ignored when auth_mode=any, in
           which case any username is allowed in as admin.

           Default: empty

           Comma-separated list of database users that are allowed to connect
           and run read-only queries on console. Thats means all SHOW commands
           except SHOW FDS.

           Default: empty.

   Connection sanity checks, timeouts
           Query sent to server on connection release, before making it
           available to other clients. At that moment no transaction is in
           progress so it should not include ABORT or ROLLBACK.

           Good choice for Postgres 8.2 and below is:

               server_reset_query = RESET ALL; SET SESSION AUTHORIZATION DEFAULT;

           for 8.3 and above its enough to do:

               server_reset_query = DISCARD ALL;

           How long to keep released connections available for immidiate
           re-use, without running sanity-check queries on it. If 0 then the
           query is ran always.

           Default: 30

           Simple do-nothing query to check if the server connection is alive.

           If an empty string, then sanity checking is disabled.

           Default: SELECT 1;

           The pooler will try to close server connections that have been
           connected longer than this. Setting it to 0 means the connection is
           to be used only once, then closed. [seconds]

           Default: 3600

           If a server connection has been idle more than this many seconds,
           and there are too many connections in the pool, this one can be
           dropped. [seconds]

           Default: 600

           If connection and login won’t finish in this amount of time, the
           connection will be closed. [seconds]

           Default: 15

           If login failed, because of failure from connect() or
           authentication that pooler waits this much before retrying to
           connect. [seconds]

           Default: 15

           If a client connects but does not manage to login in this amount of
           time, it will be disconnected. Mainly needed to avoid dead
           connections stalling SUSPEND and thus online restart. [seconds]

           Default: 60

           If the automatically created (via "*") database pools have been
           unused this many seconds, they are freed. The negative aspect of
           that is that their statistics are also forgotten. [seconds]

           Default: 3600

   Dangerous timeouts
       Setting following timeouts cause unexpected errors.

           Queries running longer than that are canceled. This should be used
           only with slightly smaller server-side statement_timeout, to apply
           only for network problems. [seconds]

           Default: 0 (disabled)

           Maximum time queries are allowed to spend waiting for execution. If
           the query is not assigned to a server during that time, the client
           is disconnected. This is used to prevent unresponsive servers from
           grabbing up connections. [seconds]

           Default: 0 (disabled)

           Client connections idling longer than this many seconds are closed.
           This should be larger than the client-side connection lifetime
           settings, and only used for network problems. [seconds]

           Default: 0 (disabled)

   Low-level network settings
           Internal buffer size for packets. Affects size of TCP packets sent
           and general memory usage. Actual libpq packets can be larger than
           this so, no need to set it large.

           Default: 2048

           Backlog argument for listen(2). Determines how many new unanswered
           connection attempts are kept in queue. When queue is full, futher
           new connections are dropped.

           Default: 128

           How many times to process data on one connection, before
           proceeding. Without this limit, one connection with a big resultset
           can stall PgBouncer for a long time. One loop processes one pkt_buf
           amount of data. 0 means no limit.

           Default: 5

           For details on this and other tcp options, please see man 7 tcp.

           Default: 45 on Linux, otherwise 0

           Default: not set

           Default: not set

           Default: not set

           Default: not set

           Default: not set


       This contains key=value pairs where key will be taken as a database
       name and value as a libpq connect-string style list of key=value pairs.
       As actual libpq is not used, so not all features from libpq can be used
       (service=, .pgpass).

       Database name can contain characters [0-9A-Za-z_.-] without quoting.
       Names that contain other chars need to be quoted with standard SQL
       ident quoting: double quotes where "" is taken as single quote.

       "\*" acts as fallback database: if the exact name does not exist, its
       value is taken as connect string for requested database. Such
       automatically created database entries are cleaned up if they stay idle
       longer then the time specified in autodb_idle_timeout parameter.

   Location parameters
           Destination database name.

           Default: same as client-side database name.

           IP address to connect to.

           Default: not set, meaning to use a Unix socket.

           Default: 5432

       user, password
           If user= is set, all connections to the destination database will
           be done with the specified user, meaning that there will be only
           one pool for this database.

           Otherwise PgBouncer tries to log into the destination database with
           client username, meaning that there will be one pool per user.

   Pool configuration
           Set maximum size of pools for this database. If not set, the
           default_pool_size is used.

           Query to be executed after a connection is established, but before
           allowingf the connection to be used by any clients. If the query
           raises errors, they are logged but ignored otherwise.

   Extra parameters
       They allow setting default parameters on server connection.

       Note that since version 1.1 PgBouncer tracks client changes for their
       values, so their use in pgbouncer.ini is deprecated now.

           Ask specific client_encoding from server.

           Ask specific datestyle from server.

           Ask specific timezone from server.


       PgBouncer needs its own user database. The users are loaded from a text
       file that should be in same format as PostgreSQL’s pg_auth/pg_pwd file.

           "username1" "password" ...
           "username2" "md5abcdef012342345" ...

       There shoud be at least 2 fields, surrounded by double quotes. The
       first field is the username and the second is either a plain-text or a
       MD5-hashed password. PgBouncer ignores the rest of the line.

       This file format allows you to directly use the existing PostgreSQL
       authentication files in the Postgres data directory.


   Minimal config
           template1 = host= dbname=template1

           pool_mode = session
           listen_port = 6543
           listen_addr =
           auth_type = md5
           auth_file = users.txt
           logfile = pgbouncer.log
           pidfile =
           admin_users = someuser
           stats_users = stat_collector

   Database defaults

           ; foodb over unix socket
           foodb =

           ; redirect bardb to bazdb on localhost
           bardb = host= dbname=bazdb

           ; access to destination database will go with single user
           forcedb = host= port=300 user=baz password=foo client_encoding=UNICODE datestyle=ISO


       pgbouncer(1) - manpage for general usage, console commands.