Wiki / Connection Parameters / Timeouts and keepalives
keepalives_interval
Controls the number of seconds after which a TCP keepalive message that is not acknowledged by the server should be retransmitted. A value of zero uses the system default. This parameter is ignored for connections made via a Unix-domain socket, or i…
Reading PostgreSQL 18.6.
Description
Controls the number of seconds after which a TCP keepalive message that is not acknowledged by the server should be retransmitted. A value of zero uses the system default. This parameter is ignored for connections made via a Unix-domain socket, or if keepalives are disabled. It is only supported on systems where TCP_KEEPINTVL or an equivalent socket option is available, and on Windows; on other systems, it has no effect.
- Client library
- libpq 18.6
- Manual definition
- Documented
- Source environment fallback
- None declared in the option table
- Compiled fallback expression
- NULL
Usage
keepalives_intervalDefault resolution and service-file precedence
The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.
Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\postgresql\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .
Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults.
Environment variable evidence
Manual definition
keepalives_interval-
Controls the number of seconds after which a TCP keepalive message that is not acknowledged by the server should be retransmitted. A value of zero uses the system default. This parameter is ignored for connections made via a Unix-domain socket, or if keepalives are disabled. It is only supported on systems where
TCP_KEEPINTVLor an equivalent socket option is available, and on Windows; on other systems, it has no effect.
Related entries
Documentation and source
- 18.6 English manual · libpq-connect.html
- 18.6 libpq connection option declarations
- 18.6 English manual · libpq-envars.html
- 18.6 English manual · libpq-pgservice.html
Source build
- Version
- 18.6
- Build
- https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2
- Source fingerprint
ee8d1a3612338fd9adf250730cb640fcc5233b5491337cc00a316a44e3a0b9f8
Compare versions
PostgreSQL 17 → 18: unchanged.
Compares recorded interfaces and attributes. Source fingerprints and build metadata are excluded; an absent sample is not proof of the introduction or removal release.
Related entries
Export JSON · Back to Connection Parameters · Recorded in PostgreSQL 10 through 20; the first sample is not necessarily its introduction.