PgBouncer

Lightweight connection pooler for PostgreSQL.

Homepage: https://www.pgbouncer.org/

Sources, bug tracking: https://github.com/pgbouncer/pgbouncer

Building

PgBouncer depends on few things to get compiled:

• GNU Make 3.81+
• Libevent 2.0+
• pkg-config
• OpenSSL 1.0.1+ for TLS support
• (optional) c-ares as alternative to Libevent's evdns
• (optional) PAM libraries

When dependencies are installed just run:

$ ./configure --prefix=/usr/local
$ make
$ make install

If you are building from Git, or are building for Windows, please see separate build instructions below.

DNS lookup support

PgBouncer does host name lookups at connect time instead of just once at configuration load time. This requires an asynchronous DNS implementation. The following table shows supported backends and their probing order:

backend	parallel	EDNS0 (1)	/etc/hosts	SOA lookup (2)	note
c-ares	yes	yes	yes	yes	IPv6+CNAME buggy in <=1.10
udns	yes	yes	no	yes	IPv4 only
evdns, libevent 2.x	yes	no	yes	no	does not check /etc/hosts updates
getaddrinfo_a, glibc 2.9+	yes	yes (3)	yes	no	N/A on non-glibc
getaddrinfo, libc	no	yes (3)	yes	no	N/A on Windows, requires pthreads

1. EDNS0 is required to have more than 8 addresses behind one host name.
2. SOA lookup is needed to re-check host names on zone serial change.
3. To enable EDNS0, add options edns0 to /etc/resolv.conf.

c-ares is the most fully-featured implementation and is recommended for most uses and binary packaging (if a sufficiently new version is available). Libevent's built-in evdns is also suitable for many uses, with the listed restrictions. The other backends are mostly legacy options at this point and don't receive much testing anymore.

By default, c-ares is used if it can be found. Its use can be forced with configure --with-cares or disabled with --without-cares. If c-ares is not used (not found or disabled), then specify --with-udns to pick udns, else Libevent is used. Specify --disable-evdns to disable the use of Libevent's evdns and fall back to a libc-based implementation.

PAM authentication

To enable PAM authentication, ./configure has a flag --with-pam (default value is no). When compiled with PAM support, a new global authentication type pam is available to validate users through PAM.

systemd integration

To enable systemd integration, use the configure option --with-systemd. This allows using Type=notify service units. See etc/pgbouncer.service for an example.

Building from Git

Building PgBouncer from Git requires that you fetch the libusual submodule and generate the header and configuration files before you can run configure:

$ git clone https://github.com/pgbouncer/pgbouncer.git
$ cd pgbouncer
$ git submodule init
$ git submodule update
$ ./autogen.sh
$ ./configure ...
$ make
$ make install

Additional packages required: autoconf, automake, libtool, pandoc

Building on Windows

The only supported build environment on Windows is MinGW. Cygwin and Visual $ANYTHING are not supported.

To build on MinGW, do the usual:

$ ./configure ...
$ make

If cross-compiling from Unix:

$ ./configure --host=i586-mingw32msvc ...

Running on Windows

Running from the command line goes as usual, except that the -d (daemonize), -R (reboot), and -u (switch user) switches will not work.

To run PgBouncer as a Windows service, you need to configure the service_name parameter to set name for service. Then:

$ pgbouncer -regservice config.ini

To uninstall service:

$ pgbouncer -unregservice config.ini

To use the Windows event log, set syslog = 1 in the configuration file. But before that you need to register pgbevent.dll:

$ regsvr32 pgbevent.dll

To unregister it, do:

$ regsvr32 /u pgbevent.dll