Provided by: pgbouncer_1.5.4-4_amd64 bug

NAME

       pgbouncer - Lightweight connection pooler for PostgreSQL.

SYNOPSIS

       [databases]
       db = ...

       [pgbouncer]
       ...

DESCRIPTION

       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 line.

SECTION [PGBOUNCER]

   Generic settings
       logfile
           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.

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

           Default: not set.

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

           Addresses can be specified numerically (IPv4/IPv6) or by name.

           Default: not set

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

           Default: 6432

       unix_socket_dir
           Specifies location for Unix sockets. Applies to both listening socket and server
           connections. If set to an empty string, Unix sockets are disabled. Required for online
           reboot (-R) to work. Note: Not supported on Windows machines.

           Default: /tmp

       unix_socket_mode
           Filesystem mode for unix socket.

           Default: 0777

       unix_socket_group
           Group name to use for unix socket.

           Default: not set

       user
           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

       auth_file
           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.

       auth_type
           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.

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

           plain
               Clear-text password is sent over wire.

           trust
               No authentication is done. Username must still exist in auth_file.

           any
               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.

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

           session
               Server is released back to pool after client disconnects. Default.

           transaction
               Server is released back to pool after transaction finishes.

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

       max_client_conn
           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

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

           Default: 20

       min_pool_size
           Add more server connections to pool if below this number. Improves behaviour when
           usual load comes suddenly back after period of total inactivity.

           Default: 0 (disabled)

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

           Default: 0 (disabled)

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

           Default: 5.0

       server_round_robin
           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

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

           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

       disable_pqexec
           Disable Simple Query protocol (PQexec). Unlike Extended Query protocol, Simple Query
           allows multiple queries in one packet, which allows some classes of SQL-injection
           attacks. Disabling it can improve security. Obviously this means only clients that
           exclusively use Extended Query protocol will stay working.

           Default: 0

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

           Default: 0

       syslog_ident
           Under what name to send logs to syslog.

           Default: pgbouncer (program name)

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

           Default: daemon

       log_connections
           Log successful logins.

           Default: 1

       log_disconnections
           Log disconnections with reasons.

           Default: 1

       log_pooler_errors
           Log error messages pooler sends to clients.

           Default: 1

       stats_period
           Period for writing aggregated stats into log.

           Default: 60

   Console access control
       admin_users
           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

       stats_users
           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
       server_reset_query
           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.

           A 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;

           When transaction pooling is used, the server_reset_query should be empty, as clients
           should not use any session features.

           Default: DISCARD ALL

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

           Default: 30.0

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

           If an empty string, then sanity checking is disabled.

           Default: SELECT 1;

       server_lifetime
           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: 3600.0

       server_idle_timeout
           If a server connection has been idle more than this many seconds it will be dropped.
           If 0 then timeout is disabled. [seconds]

           Default: 600.0

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

           Default: 15.0

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

           Default: 15.0

       client_login_timeout
           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: 60.0

       autodb_idle_timeout
           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: 3600.0

       dns_max_ttl
           How long the DNS lookups can be cached. If a DNS lookup returns several answers,
           pgbouncer will robin-between them in the meantime. Actual DNS TTL is ignored.
           [seconds]

           Default: 15.0

       dns_zone_check_period
           Period to check if zone serial has changed.

           PgBouncer can collect dns zones from hostnames (everything after first dot) and then
           periodically check if zone serial changes. If it notices changes, all hostnames under
           that zone are looked up again. If any host ip changes, it’s connections are
           invalidated.

           Works only with UDNS backend (--with-udns to configure).

           Default: 0.0 (disabled)

   Dangerous timeouts
       Setting following timeouts cause unexpected errors.

       query_timeout
           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: 0.0 (disabled)

       query_wait_timeout
           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: 0.0 (disabled)

       client_idle_timeout
           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: 0.0 (disabled)

       idle_transaction_timeout
           If client has been in "idle in transaction" state longer, it will be disconnected.
           [seconds]

           Default: 0.0 (disabled)

   Low-level network settings
       pkt_buf
           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

       max_packet_size
           Maximum size for Postgres packets that PgBouncer allows through. One packet is either
           one query or one resultset row. Full resultset can be larger.

           Default: 2147483647

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

           Default: 128

       sbuf_loopcnt
           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

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

           Default: 45 on Linux, otherwise 0

       tcp_socket_buffer
           Default: not set

       tcp_keepalive
           Turns on basic keepalive with OS defaults.

           On Linux, the system defaults are tcp_keepidle=7200, tcp_keepintvl=75, tcp_keepcnt=9.
           They are probably similar on other OS-es.

           Default: 1

       tcp_keepcnt
           Default: not set

       tcp_keepidle
           Default: not set

       tcp_keepintvl
           Default: not set

SECTION [DATABASES]

       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
       dbname
           Destination database name.

           Default: same as client-side database name.

       host
           Hostname or IP address to connect to. Hostnames are resolved on connect time, the
           result is cached per dns_max_ttl parameter. If DNS returns several results, they are
           used in round-robin manner.

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

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

       connect_query
           Query to be executed after a connection is established, but before allowing 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.

       client_encoding
           Ask specific client_encoding from server.

       datestyle
           Ask specific datestyle from server.

       timezone
           Ask specific timezone from server.

AUTHENTICATION FILE FORMAT

       PgBouncer needs its own user database. The users are loaded from a text file in following
       format:

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

       There should 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-hidden password. PgBouncer ignores
       the rest of the line.

       This file format is equivalent to text files used by PostgreSQL 8.x for authentication
       info, thus allowing PgBouncer to work directly on PostgreSQL authentication files in data
       directory.

       Since PostgreSQL 9.0, the text files are not used anymore. Thus the auth file needs to be
       generated. See ./etc/mkauth.py for sample script to generate auth file from pg_shadow
       table.

       PostgreSQL MD5-hidden password format:

           "md5" + md5(password + username)

       So user admin with password 1234 will have MD5-hidden password
       md545f2603610af569b6155c45067268c6b.

EXAMPLE

   Minimal config
           [databases]
           template1 = host=127.0.0.1 dbname=template1

           [pgbouncer]
           pool_mode = session
           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
           stats_users = stat_collector

   Database defaults
           [databases]

           ; foodb over unix socket
           foodb =

           ; redirect bardb to bazdb on localhost
           bardb = host=127.0.0.1 dbname=bazdb

           ; access to destination database will go with single user
           forcedb = host=127.0.0.1 port=300 user=baz password=foo client_encoding=UNICODE datestyle=ISO

SEE ALSO

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

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

                                            06/18/2013                               PGBOUNCER(5)